Showing posts with label Computer. Show all posts
Showing posts with label Computer. Show all posts

What is windows operating system and Types of Windows OS

What is windows operating system and Types of Windows OS

What is windows operating system and Types of Windows OS

Windows is an operating system designed by Microsoft. The operating system is what permits you to use a computer. Windows comes preloaded on most new personal computers (PCs), which helps to make it the most popular operating system in the world. You can also install windows manually in your computer.

Windows makes it possible to complete all types of everyday tasks on your computer. For example, you can use Windows to browse the Internet, check your email, edit digital photos, listen to music, Create Project reports, play games, and do much more.

Windows is also used in many offices because it gives you access to productivity tools such as calendars, word processors, and spreadsheets.

Microsoft released the first version of Windows in the mid-1980s. There have been many versions of Windows since then, but the most recent ones include Windows 10 (released in 2015), Windows 8 (2012), Windows 7 (2009), Windows Vista (2007), and Windows XP (2001).

List of Windows Client OS with their Version Numbers

Operating System

Version Number

Windows 1.0
Windows 2.0
Windows 3.0
Windows NT 3.1
Windows for Workgroups 3.11
Windows NT Workstation 3.5
Windows NT Workstation 3.51
Windows 95
Windows NT Workstation 4.0
Windows 98
Windows 98 Second Edition
Windows Me
Windows 2000 Professional
Windows XP
Windows Vista
Windows 7
Windows 8.1
Windows 10

Different Types of Windows Operating Systems

Computer users have differing requirements. While a distinctive business needs to manage network permissions and give many users concurrent access to shared resources, a home user may simply use his computer to check email and play an random games. Microsoft markets several versions of Windows to serve the needs of these markets. Each edition has a different price point and feature set from the others.

Home Computers

Home editions of Windows such as Windows 7 Starter and Windows 7 Home Premium or Windows 10 provide the basic functionality that personal computers require. These include the ability to run software, play games, access the Internet and view or manipulate media such as music, videos and images. To keep consumers' costs down, these editions of Windows do not include some of the advanced features that business users require.

Business Computers

Business computers often require features not needed on standard home machines. For example, Windows 7 Professional or ultimate editions includes a feature called "Windows XP Mode" for running legacy software. It also includes the ability to act as a host for the Remote Desktop application and has a self-encrypting file system to prevent data loss from theft. Windows 7 Enterprise features data encryption for removable storage devices. It also has the ability to run on a computer with no hard drive by booting from a virtual image hosted on a server.

Servers Computer

Business networks may have many users logged in to their computers concurrently during the working day. Each user needs to access resources such as databases, intranet websites, email, Sharing files and Internet gateways. In addition, each user has her own password and access permissions. The powerful computer needed to manage network access for a large user base is called a server. Because servers perform very different roles from standard business computers, they require different operating systems. The Windows Server product line is Microsoft's offering for servers.

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What is Cache Memory. Types and functions of cache memory?

What is Cache Memory. Types and functions of cache memory?

Cache Memory

Cache Memory

The Cache Memory is the Memory which is very near to the central processing unit , all the Fresh Commands are Stored into the Cache Memory. The Cache Memory is committed for storing the input which is given by the user and which is essential for the CPU to Implement a Task. But the Capacity of the Cache Memory is too small in compare to Memory and Hard Disk.

Prominence of Cache memory

The cache memory lies in the path between the processor and the memory. The cache memory consequently, has lesser access time than memory and is faster than the main memory. A cache memory have an access time of 100ns, while the main memory may have an access time of 700ns.

The cache memory is very expensive and hence is limited in capacity. Earlier cache memories were available separately but the microprocessors contain the cache memory on the chip itself.

The need for the cache memory is due to the mismatch between the speeds of the main memory and the CPU. The CPU clock as discussed earlier is very fast, whereas the main memory access time is comparatively slower. Hence, no matter how fast the processor is, the processing speed depends more on the speed of the main memory (the strength of a chain is the strength of its weakest link). It is because of this reason that a cache memory having access time closer to the processor speed is introduced. 

The cache memory stores the program (or its part) currently being executed or which may be executed within a short period of time. The cache memory also stores temporary data that the CPU may frequently require for manipulation.

The cache memory works according to various algorithms, which decide what information it has to store. These algorithms work out the probability to decide which data would be most frequently needed. This probability is worked out on the basis of past observations.

It acts as a high speed buffer between CPU and main memory and is used to temporary store very active data and action during processing since the cache memory is faster than main memory, the processing speed is increased by making the data and instructions needed in current processing available in cache.
types of cache memory

A computer can have different levels and sizes of cache depending on the CPU architecture. The most common levels of cache are L1 and L2 cache, where L1 is closest to the Cpu and hence its access time is much faster compared to L2 cache , the sizes of these caches can vary from 8Kb - 128kb or even 256Kb in modern systems.

Another mode of caching is Disk Caching

Disk caching works under the same principle as memory caching, but instead of using high-speed SRAM, a it uses conventional main memory. The most recently accessed data from the hard drive (as well as adjacent sectors) is saved in a memory buffer. When a program needs to access data from the disk, it first checks the disk cache to see if the data is there. Disk caching can dramatically improve the performance of software. Because accessing a byte of data in RAM can be thousands of times faster than accessing a byte on a hard disk.

The effectiveness of any cache is determined by its hit rate. The higher the hit rate the better the performance of cpu and the better the caching algorithm implemented.

Two most common algorithm for caching are

· Least Frequently Used (LFU): This cache algorithm uses a counter to keep track of how often an entry is accessed.
· Least Recently Used (LRU): This cache algorithm keeps recently used items near the top of cache.

Recall: A lower size cache with high hit ratio, is far better than a large size cache with poor hit ratio. 

A CPU cache is a cache used by the central processing unit (CPU) of a computer to reduce the average time to access data from the main memory. The cache is a smaller, faster memory which stores copies of the data from frequently used main memory locations. Most CPUs have different independent caches, including instruction and data caches, where the data cache is usually organized as a hierarchy of more cache levels (L1, L2, etc.). 

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What is Difference Between Pixel and Resolution

What is Difference Between Pixel and Resolution

Resolution Vs Pixel Density in Displays

Pixel vs Resolution

Summary: Difference Between Pixel and Resolution is that pixel is the smallest element in an electronic image. The greater the number of pixels the camera uses to capture a picture, the better the quality of the picture. While Resolution is the number of horizontal and vertical pixels in a display device. A digital camera’s resolution is defined in pixels.


A pixel (short for picture element) is the smallest element in an electronic image. The greater the number of pixels the camera uses to capture a picture, the better the quality of the picture. Digital camera resolutions range from about 4 million to more than 16 million pixels (MP).
Usually displays are measured in size(in centimeters and inches). Here we only measure the diagonal size and not the horizontal or vertical size of the screen. There is also another important property of display which is the resolution. Resolution refers to size of the display in terms of pixels. E.g. Resolution of 800×600 pixels means that the there are 800 pixels horizontally and 600 pixels vertically. So therefore there are a total of 480000 pixel in the display.
Pixel is just an element of the picture that plays an important role to complete the image. The word ‘pixel’ was first published by Frederic C. Billingsley in 1965. The measurement of the screen can be described through pixels. Hence, the size of the image also depends on the number of pixels, the larger the number of pixels your image is having the greater the size will be.

Pixel Density

Many of us are not aware of the importance of Pixel Density in displays. It is the thing which describes the sharpness and clarity. Pixel Density is usually measured in PPI (Pixels Per Inch) which refers to number of pixels present per inch on the display. Higher the pixel density higher is the sharpness of the content. Pixel Density is calculated based on the resolution and size of the display.
Pixel Density= Root((Horizontal Number of Pixel^2) + (Vertical Number of Pixel^2))/Screen Size


One factor that affects the quality of digital camera photos is its resolution. Resolution is the number of horizontal and vertical pixels in a display device. A digital camera’s resolution is defined in pixels. Resolution is made up of all the elements (pixels) combined together to form a quality image. The greater the resolution is the better you will get the quality of your picture. Resolution describes the elements or pixels in an image. You can measure resolution in three difference ways, Sample per inch (spi, scanners) or Pixel per inch (ppi, monitors) or Dots per inch (dpi, printers).

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What is the Difference Between Impact Printers and Non-Impact Printers?

Impact Printers and Non-Impact
Printer Technology has advanced greatly over the past few decades. Yesterday's impact printers were noisy devices that either churned out blocky documents mixing text and graphics or generated attractive text, but without the ability to print graphics, varying fonts or even varied text sizes. Many of today's non-impact printers are almost whisper quiet and generate entire pages in just a few seconds. However, impact printer technology still has its benefits.

Impact Printers
Impact printers operate by having an element strike the paper. An impact printer forms characters and graphics on a piece of paper by striking a mechanism against an inked ribbon that physically contacts the paper. Impact printers are ideal for printing multipart forms because they easily print through many layers of paper. Two commonly used types of impact printers are dot-matrix printers and line printers.

Impact Printer
A dot-matrix printer produces printed images when tiny wire pins on a print head mechanism strike an inked ribbon. When the ribbon presses against the paper, it creates dots that form characters and graphics. Dot-matrix printers typically use continuousform paper, in which thousands of sheets of paper are connected together end to end. The pages have holes along the sides to help feed the paper through the printer. The speed of most dot-matrix printers ranges from 375 to 1100 characters per second (cps), depending on the desired print quality.

A line printer is a high-speed impact printer that prints an entire line at a time. The speed of a line printer is measured by the number of lines per minute (lpm) it can print. Some line printers print as many as 3,000 lpm.

 For instance, to make a capital "I" in a serif font, the top and bottom pin would fire, then every pin would fire, then the top and bottom pin would fire. The pins strike an ink-impregnated ribbon and press it into the paper, leaving a mark. One of the problems with dot matrix printing technology is that there are gaps between the pins, leading to output that has a number of gaps and looks incomplete. 

Daisy wheel impact printers pressed a wheel with pre-formed characters, much like the mechanism in an electrical typewriter, against a ribbon to form an impression on a page. They produced very high quality output but could only print in a single font and character size. In addition, they were extremely slow, with some printing just 10 characters per second.

Non-Impact Printers
The printheads of non-impact printers do not strike the page. In an inkjet printer, a printhead sits a small distance above the page and either sprays ink or pops a bubble of ink onto the paper. Laser and light-emitting diode printers use electrical charges to transfer dry toner particles from a light sensitive drum to a piece of paper and then melt the toner onto it.

NON-Impact Printers
Benefits of Impact Printers
Impact printers have a couple of benefits. The first is that since they use pressure to generate an image, they work with multipart forms that either have leaves of carbon paper or use carbon-imprinted paper. The second is that since they print one line at a time instead of one page at a time, their paper feed mechanisms are designed to let them use continuous forms.

Non-Impact Printer
A nonimpact printer forms characters and graphics on a piece of paper without actually striking the paper. Some nonimpact printers spray ink, while others use heat or pressure to create images. Commonly used nonimpact printers are ink-jet printers, photo printers, laser printers, thermal printers, mobile printers, plotters, and large-format printers.

An ink-jet printer is a type of nonimpact printer that forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper. Ink-jet printers have become a popular type of color printer for use in the home. Ink-jet printers produce text and graphics in both black-and-white and color on a variety of paper types.

A photo printer is a color printer that produces photo-lab-quality pictures. Some photo printers print just one or two sizes of photos, for example, 3 3 5 inches and 4 3 6 inches. Others print up to letter size, legal size, or even larger. Many photo printers use ink-jet technology. With models that can print lettersized documents, users connect the photo printer to their computer and use it for all their printing needs.

A laser printer is a high-speed, high-quality nonimpact printer.Laser printers for personal computers ordinarily use individual sheets of paper stored in one or more removable trays that slide in the printer case.

Non-impact printers have advanced to a point that they are better than impact printers at just about everything other than feeding continuous paper and working with multi-part forms. They have much higher resolutions since, instead of using metal pins, they can use drops of ink measured in picoliters or toner particles measured in micrometers. Non-impact printers are also much quieter, making it possible for them to be used out in the open in office settings.

Difference Between Impact Printers and Non-Impact Printers.
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Access Remote Desktops "Jump Clients" Overview

Jump Clients
Access remote desktops, laptops, POS systems, kiosks and servers, even if no one is present to give you control. Jump Clients work regardless of network location.

Secure Remote Access, Regardless of Network Location
Jump Clients let you control remote computers even when you don’t control the remote network.

Just install a Jump Client on each system you need to access. You’ll be able to control it wherever it goes.

With Jump Clients support reps can access the remote systems without requiring the person on the other end of the session to be technical.

Secure Remote Access, Regardless of Network Location
(Jump Clients are a component of Bomgar’s patent-pending Jump Technology.)

Wistia video thumbnail - Feature: Jump Client Management

Jump Clients let you control remote computers even when you don’t control the remote network.

Just install a Jump Client on each system you need to access. You’ll be able to control it wherever it goes.

With Jump Clients support reps can access the remote systems without requiring the person on the other end of the session to be technical.

Multi-Platform Remote Access, Even from Android and iOS Devices

Control Remote Desktops and Servers from an iPad Securely control remote desktops and servers from an iPad

Jump Clients can be installed on Windows, Mac, or Linux computers, as well as Android phones and tablets. You can access them from any platform Bomgar supports.

So not only can the remote systems you're supporting be located anywhere, the support technicians can be, too.

Whether you’re offering support from a laptop, or from an Android or iOS device, you can stay productive while mobile.
Manage and Mass Deploy Jump Clients

Jump Clients can be mass deployed to Windows, Mac and Linux desktops or servers. To help with finding and identifying computers later, you can add a group name and comments when you deploy them.

You can create a default installer. Or you can use mass deployment scripts to pull in variables from other sources to modify the Jump Client parameters during installation.

Integrated Remote Access for Your Systems Management Platform
Jump Clients Enable Remote Access Jump Clients enable remote access regardless of network location

Support organizations can improve service levels, centralize support processes and strengthen compliance by integrating Bomgar with their systems management platform.

Once integrated, Bomgar enables technicians to offer proactive system support to all your Jump Clients directly from your systems management tool.

Bomgar can be launched from the ticket or system record. At the end of the session, Bomgar updates the ticket with details from each Bomgar remote support session, including links to session recordings, file transfer details, work notes, system information and post-session survey results.

Use Schedules to Limit Jump Client Access to Specific Times
There are two options to restrict access to Jump Clients. First, administrators can use time schedules to control periodic access to Jump Clients. Access schedules dictate the windows of time representatives are allowed to access certain Jump Clients.

You can also allow reps to deploy Jump Clients that automatically uninstall after a defined period of time.

Using Jump Client access schedules can protect your client from interruption and help your support organization conform to customers’ support needs . Both schedules and automatic expiration can help satisfy PCI compliance or prevent business users from being interrupted during peak hours.

Wake-On-LAN Support for Jump Clients in a Network
Wake-on-LAN (WOL) Support Wake-on-LAN (WOL) support lets you turn on remote computers

Support organizations can save on power costs by turning computers off after hours. With Bomgar, powering systems on/off can be handled remotely with Wake-on-LAN (WOL) support.

With wake-on-LAN support, you can broadcast Wake-on-LAN (WOL) packets through another Jump Client on the same network. Use of wake-on-LAN depends on user permissions and may not be supported in all environments.

Share Jump Clients Across Support Teams
For scenarios in which multiple groups need to access the same group of desktops, you can share a team’s Jump Clients across support teams and Embassies.

Your group policies determine how members of each team can interact with the remote computer.

Sharing Jump Clients allows you to give both internal reps and vendors access to the same system without complicating team structures.

Use Endpoints to Define How Sessions Begin
When you use Jump Clients to access servers and back end systems, you want to launch right into remote control. No one is present on the other end of a server for you to interrupt. But when you access remote desktops, you may want to display a prompt in case an end-user is present.

Support Session Policies let you define how a session begins based on the endpoint being supported.

With policies at the Jump Client level, you can choose to display a prompt if the remote desktop is one at which an end-user may be present. If the endpoint is a server, you can set the session policy up with no prompt.
Once Connected, Powerful Tools Are at Your Fingertips

When you connect to a remote desktop or server, Bomgar puts powerful tools at your disposal. Tools include:

    Command shell
    File Transfer
    Multi-monitor support
    Privacy screen
    Registry editor
    Special actions
    System information
    UAC elevation

Plus, you can control multiple systems simultaneously for maximum efficiency.
Report on Remote Access Sessions

Bomgar's logging and recording capabilities capture extensive detail about sessions performed through Jump Clients. These reports give administrators critical visibility into support activity.

Reports include IP information, system information, files transferred, chat transcripts, and many other details about the support session. Bomgar can even create video recordings of support sessions.

With Bomgar, you'll replace legacy remote access tools with a complete solution designed for the needs of security-conscious support organizations. Bomgar enables support representatives to access, diagnose, control and fix remote computers and mobile devices. Highlighted features are below.

Remote Control & Screen Sharing - the Core of Support
The core of remote support is seeing and controlling the remote computer. With Bomgar Remote Support, you can see your customer's screen and fully interact with the remote desktop.

Request remote control of multiple computers, view attached monitors, and use advanced screen sharing tools.

Remote Control and Screen Sharing
Customer Tech Support

Use chat support, screen sharing, CRM integration, and skills-based routing to increase support staff productivity. Bomgar Remote Support includes customizable surveys and support portals.

Use Bomgar for Customer Tech Support
Internal IT Support

Perform desktop support and server maintenance securely. Replace RDP, VNC, and other hard-to-audit remote control tools with a cross-platform support tool.

Use Bomgar for Internal IT Support
Help Desk Administration
Help Desk Integrations

Create queues, portals, teams, and policies to standardize technical support services. Manage technicians with integrated identity management and group policies.

Help Desk Administration
Monitor and Audit

Wistia video thumbnail - Demo: Monitor and Audit Remote Support Sessions

Monitor support activity in real time. Track customer satisfaction. Record every remote support session. And collect a detailed audit trail of each interaction.

Auditing Remote Support

Wistia video thumbnail - Demo: Collaborate during Remote Support Sessions

Share sessions between technicians, developers, or even outside vendors so that they can see the issue and troubleshoot together, helping support incidents get resolved faster.

Collaborative Remote Support

Wistia video thumbnail - Bomgar Button Demo

Embedding chat and remote support in your website, desktops, Windows programs, and mobile apps makes it easy for customers and employees to get help.

Embeddables for Remote Support

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Online File Storage Sites for Free

List of the best free on line file storage sites. More than just external hard drives, many of these sites are collaboration platforms that you can use to share documents with friends.
.Box: gives you 5 GB of storage for free and lets you organize your files into folders in the cloud, just like you would on your desktop. You can share links or entire file folders with others and see when they’ve been viewed.
.Bitcasa: stores up to 10 GB worth of free files, photos, playlists, videos and docs that can be accessed from any device (and reportedly goes up to infinity for paying customers).
.Dropbox: is a secure place to keep photos, documents, and videos that you can access from your computer, smartphone, or tablet. You can share the files with your social networks as well. It comes with 2 GB of free storage (or up to 18 GB if you refer a friend).
.Evernote: saves all of your notes, web clips, files, scanned documents, and images. You can search for the documents by keyword, access them from any device, and share them with friends. The storage process here is a little different: free users can store up to 100,000 notes (up to 25 mb each), 250 synchronized notebooks, 10,000 tags, and 100 saved searches.
.Google Drive: syncs documents, spreadsheets, presentations, and videos from your computer and mobile devices. It connects to Google+ and Gmail for collaboration and sharing. It has a free storage limit of up to 5 GB that’s shared between Google Drive and Google+ Photos.
.iCloud: is just for iOS devices, but it syncs all your music, photos, apps, calendars, documents, and other files and makes them sharable with friends. It comes with 5 GB of free cloud storage. Bonus: the photos in your Photo Stream and whatever music, movies, TV shows, apps, and books you buy from iTunes don’t count against your storage limit.
.Mega: Internet outlaw Kim Dotcom released this service one year after the U.S. government shut down its predecessor, MegaUpload, for facilitating copyright infringement. The new tool promises “state of the art, browser-based encryption technology” and a whopping 50 GB of free cloud storage.
.SkyDrive: offers 7 GB of free cloud storage for photos, documents, and other files and works on any device. Windows 8 users can log in with their Microsoft accounts to view photos and files, edit and share Office documents, and share the files with friends.
If you still need extra storage space, these companies will be more than happy to sell it to you. But unless you’re the Library of Congress, this should be enough to get you started.
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Learn difference between Network OS and Distributed OS?

Network OS is used to manage networked computers, means there would be a server and one or more computers will be managed by that server like in your college, you might have got one dedicated server and it will manage your individual computers or laptop.

Distributed OS is one where all of computers that are connected can share in tasks.For ex. if you and your friend are connected each other using distributed OS then you can use a program which is actually on someone Else's computer.This is the reason distributed OS needs more RAM & High speed processor.

In case of Networked OS,connected computers share some resources but not that much like Distributed OS, rather the server provides the necessary services for the connected computers in Networked OS.

Network Network OS is used to manage Networked computer systems and create,maintain and transfer files in that Network.
Distributed OS is also similar to Networked OS but in addition to it the platform on which it is running should have high configuration such as more capacity RAM, High speed Processor.

The main difference between the DOS and the NOS is the transparent issue:

– How aware are users of the fact that multiple computers are
being used?
• Network OS:
– Users are aware where resources are located
– Network OS is built on top of centralized OS.
– Handles interfacing and coordination between local OSs.

• Distributed OS:
– Designed to control and optimize operations and resources in
distributed system.

Initially, computers were built to operate as a singular entity; having discrete resources and individual operating system. Although the use of multiple computers to solve a single problem is not unheard of, it is often a human’s job to subdivide the problem into manageable chunks that the computers can separately work on.

A distributed OS is just an improvement of the original concept. But instead of a human cutting up the job, the OS is smart enough to know which computers are overloaded and which ones are idle. It would then balance the tasks available so that each computer in the group is sharing equal load. 

This is good for maximizing the usefulness of each computer. The drawback though is that you would need to upgrade all the units every so often to maintain a reasonable level of performance. There is also some software that is simply not compatible with distributed computing. They are not optimized to take advantage of multiple processes, and as such can only be processed by one computer.

The appearance of network operating systems is a direct result of the need to cut costs and control each computer in the system. Network OS does not reside on every computer, the client only has enough software to boot the hardware and contact the server. All the subsequent operations are done on the server, and the only role of the client is to relay the input and output between the server and the user.

This is very effective in controlling the installed software since clients do not have the capability to add or remove software. A network OS requires a very minimal amount of hardware on the client, although the server should be capable to handle the demands of multiple users. This means that you would not need to upgrade the clients as long as you keep the server properly maintained. This even led to the creation of thin clients or devices that cannot function on their own but are meant to work with network OS.

Depending on the needs and resources of your company, a distributed or network OS might be worth looking into. Each has its own advantages and disadvantages that you should take into consideration. A distributed OS could cost a bit more than a network OS, but a network OS cannot handle computation intensive programs due to the stress it puts in the server.
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