Unit 3 Computer Systems

What is software? unlike hardware it can’t be physically touched it’s the missing link between the computer hardware and the data which it is processing has to be “loaded” into the computer’s RAM before it can be “run” a set of pre-written instructions which the computer executes in order to perform a particular task typically written using programming languages such as C, C++, BASIC, Java etc. Unit 3 Computer Systems

Types of software Generally software can be split into two separate groupings: Unit 3 Computer Systems Computer Software Applications Software Systems Software

Systems software Unit 3 Computer Systems This type of software helps to run and organize the computer’s hardware. It includes a number of common features: Operating System (OS) Device drivers File Managers Graphical User Interface (GUI) and/or Command Line Interface (CLI) System utilities (eg diagnostic tools)

Applications software Common types of Application Software include: Office software (eg Word-processor, Spreadsheet, Database etc) Educational software (eg CAL – Computer Aided Learning) Business & Industrial software (eg CAD – Computer Aided Design) Communication software (eg , chat programs etc) Games Specialist (eg Speech recognition, route planners etc). Unit 3 Computer Systems This type of software - used in conjunction with an Operating System - performs a specific task.

Application Software selection Knowing what type of software to use can be difficult! Generally it is determined by two basic factors: The user’s requirements (what they actually need to do) The actual hardware and Operating System being used (what the computer can run). Unit 3 Computer Systems

Typical user requirements Does it perform the job I need it to do? Is it affordable and offer value for money (VFM)? Is it easy to use and learn? Does it do the job quickly and efficiently? Is it easily available? What are the license terms (eg Can I install it on more than 1 computer simultaneously…)? Does it have a good reputation? Do the producers of the software offer good user support? Are there any free updates? Is there a large installed user base? Unit 3 Computer Systems

Bespoke, Tailored or Commercial? Options which can be considered include: Commercially available solution Tailored solution Bespoke solution. Unit 3 Computer Systems Ideally user requirements should be fully met when considering a software application.

Commercially available solution Doesn’t really meet user’s requirements Gives no business advantage May have security issues. Unit 3 Computer Systems Cheapest option and immediately available Well-known and reliable products Users already familiar with software This is a commercial piece of software available publicly from a retailer. It is also sometimes called “off-the-shelf” or “shrink-wrapped”.

Tailored Solution Doesn’t meet user’s needs exactly – there will be some compromises Suffers same limitations as the package it is built upon Unit 3 Computer Systems Usually this is a commercially available software package (eg spreadsheets, databases etc) that has been adapted or automated to perform additional calculations. Cheaper option Quicker to build (not starting from scratch) Users already familiar with software

Bespoke Solution Meets user’s needs exactly Gives company a competitive edge Unit 3 Computer Systems Software written especially for a company or individual by programmers. Can be very expensive Not immediately available Needs specialist training.

Task Unit 3 Computer Systems Complete the Selection of Software Worksheet

Technical Requirements Does the computer meet the required minimum technical specification? Does the computer meet the recommended technical specification? Unit 3 Computer Systems Another consideration is whether or not the software can be used on the available computer hardware. Required – what hardware is necessary to run the software Recommended – what hardware is necessary to get the best performance out of the software.

Typical requirements specification Unit 3 Computer Systems What type of processing power is needed for each type of computer? The version of the Operating Systems required for each type of computer. The amount of RAM needed to run the application. The screen resolution required to display the application correctly (using Video Card and Monitor). How much Hard Disk space is needed to install and use the application? System requirements for Dreamweaver 8 © Macromedia, 2005

Summary What is Software? Types of Software (System & Application) Types of Application software Application Software selection Typical user requirements Bespoke, Tailored or Commercial? Technical Requirements. Unit 3 Computer Systems