computer Information: Computer How to Buy?

COMPUTER - HOW TO BUY?

• In this guide, we'll help you to look for when you think to buy a desktop on component by component basis.
• As Desktops are highly customizable, so it is better to learn about main parts and then go to manufacturer or retailer shop or site instead of looking at some specific model directly.
• Popular desktop brands are Dell, Lenovo, HP and Apple.
• Compare the desktops based on their specifications and base price.

Monitor

• Size - It is the diagonal size of the LCD screen. Larger the area, bigger the picture screen. A bigger picture is preferable for movie watching and gaming. It will increase productivity as well.
• Resolution - This is the number of pixels on the screen. For example, 24-inch display is 1920x1200 (width by length) and 22-inch display which is 1680x1050. High resolution provides better picture quality and a nice gaming experience.
• Inputs - Nowadays, monitors can accept inputs from cable as well apart from computer. They also can have USB ports.
• Stand - Some monitors provide adjustable stands but some may not.
• Recommended - 24 Inch LCD.

Operating System

• Operating System is the main software of the computer as everything will run on it in one form or other.
• There are primarily three choices: Windows, Linux, Apple OS X.
• Linux is free but people generally do not use it for home purpose.
• Apple OS X works only on Apple Desktops.
• Windows 7 is very popular among desktop users.
• Most of the computers come pre-equipped with Windows 7 Starter edition.
• Windows 8 is recently introduced and is available in market.
• Windows 7, Windows 8 come under multiple versions from starter, home basic, home premium, professional, ultimate and enterprise editions.
• As edition version increases, their features list and price increases.
• Recommended - Windows 7 Home Premium.

Optical Drive (CD / DVD / Blu-ray)

• Optical drive is the drive on a computer which is responsible to CD , DVD and Blu-ray discs.
• Nowadays, DVD burners are industry standards.
• DVD Burner can burn CD, DVD and play them.
• DVD Burner are cheaper than Blu-ray drives.
• Blu-ray drives can play HD movies but are costlier component.
• Recommended - DVD Burner.

Memory

• RAM is considered as Computer Memory as performance of a computer is directly proportional to its memory and processor.
• Today's software and operating systems require high memory.
• Today, commonly used RAM is DDR3, which operates at 1066Mhz
• As per window 7, 1 GB is the minimum RAM required to function properly.
• Recommended - 4 GB.

Hard Drive

• Hard disk is used for storage purpose. Higher the capacity, more data you can save in it.
• Nowadays, computers are equipped with 500GB, which can be extended to 2TB.
• Most hard drives in desktop operate at the standard performance speed of 7200RPM.
• Recommended - 500GB.

CPU

• Frequency (Ghz) - This determines speed of the processor. More the speed, better the CPU.
• Cores - Today's CPUs come with more than one core, which is like having more than one CPU in the computer. Programs, which can take advantage of multi-core environment will run faster on such machines.
• Brand - Intel or AMD. Both are equivalent. Intel is in lead.
• Cache - Higher the L1, L2 cache, better the CPU performance.
• Recommended - Intel Core i3 i3-3225 3.30 GHz Processor.

Computer Information: Operating System

OPERATING SYSTEM

• An operating system is a program that acts as an interface between the software and the computer hardware.
• It is an integration set of specialised programs that are used to manage overall resources and operations of the computer.
• It is a specialised software that controls and monitors the execution of all other programs that reside in the computer, including application programs and other system software.

Objectives of Operating System

• Making a computer system convenient to use in an efficient manner.
• To hide the details of the hardware resources from the users.
• To provide users a convenient interface to use the computer system.
• To act as an intermediary between the hardware and its users and making it easier for the users to access and use other resources.
• Manage the resources of a computer system.
• Keep track of who is using which resource, granting resource requests, according for resource using and mediating conflicting requests from different programs and users.
• The efficient and fair sharing of resources among users and programs.

Characteristics of Operating System

• Memory Management -- It keeps track of primary memory, i.e., what parts of it are in use by whom, what parts are not in use, etc. Allocates the memory when the process or program requests it.
• Processor Management -- Allocates the processor (CPU) to a process. De allocate processor when processor is no longer required.
• Device Management -- Keeps tracks of all devices. This is also called I/O controller. Decides which process gets the device when and for how much time.
• File Management -- Allocates the resources. Deal locates the resource. Decides who gets the resources.
• Security -- By means of passwords & similar other techniques, preventing unauthorized access to programs & data.
• Job accounting -- Keeping track of time & resources used by various jobs and/or users.
• Control over system performance -- Recording delays between requests for a service & from the system.
• Interaction with the operators -- The interaction may take place via the console of the computer in the form of instructions. Operating System acknowledges the same, do the corresponding action and inform the operation by a display screen.
• Error-detecting aids -- Production of dumps, traces, error messages and other debugging and error-detecting methods.
• Coordination between other software and users -- Coordination and assignment of compilers, interpreters, assemblers and other software to the various users of the computer systems.

Computer Information: Computer Software

COMPUTER - SOFTWARE

Software is a set of programs, which are designed to perform a well-defined function. A program is a sequence of instructions written to solve a particular problem.

There are two types of software:

• System Software
• Application Software

System Software

The system software is a collection of programs designed to operate, control and extend the processing capabilities of the computer itself. System software are generally prepared by computer manufacturers.

These softwares comprise of programs written in low level languages which interact with the hardware at a very basic level. System software serves as the interface between hardware and the end users.

Some examples of system software are Operating System, Compilers, Interpreter, Assemblers, etc.

Features of System Software are the following:

• Close to system.
• Fast in speed.
• Difficult to design.
• Difficult to understand.
• Less interactive.
• Smaller in size.
• Difficult to manipulate.
• Generally written in low-level language.

Application Software

Application softwares are the softwares that are designed to satisfy a particular need of a particular environment. All softwares prepared by us in the computer lab can come under the category of Application Software.

Application software may consist of a single program, such as a Microsoft's notepad for writing and editing simple text. It may also consist of a collection of programs, often called a software package, which work together to accomplish a task, such as a spreadsheet package.

Examples of Application softwares are the following:

• Payroll Software
• Student Record Software
• Inventory Management Software
• Income Tax Software
• Railways Reservation Software
• Microsoft Office Suite Software
• Microsoft Word
• Microsoft Excel
• Microsoft PowerPoint

Features of Application Software are the following:

• It is close to user.
• It is easy to design.
• More interactive.
• Slow in speed.
• Generally written in high-level language.
• Easy to understand.
• Easy to manipulate and use.
• Bigger in size and requires large storage space.