3. Sources of applications

An application can come from different sources. But the basic choices are

• Off-the-shelf: Purchase the complete application from a commercial source as a finished product.
• Custom: Purchase the application which is then altered to suit your requirements.
• Bespoke: Write it yourself or pay someone else to do it.

Of course you can expect the costs to rise rapidly as you move from an off the shelf product to a fully bespoke application.

Off-the-shelf (general purpose application)

A general purpose application, sometimes known as ‘off-the-shelf’ is the sort of software that youuse at home and school.Examples include word processors, spreadsheets, databases, desktop publishing packages, graphics packages etc.

This type of software tries to be a ‘jack-of-all-trades’.It provides many features that the majority of users will want e.g. formatting text, creating charts, organising tables.But it does try to be’ all things to all people’ and so there will be a vast number of features that you may never use e.g. statistical functions, mail merge.This makes the storage size of these applications fairly large.

There are several good reasons for using general purpose software:

• It is relatively cheap
• It is easily available from most computer shops
• It will have been thoroughly tested so there won’t be any serious problems or bugs
• There will be lots of user support i.e. books, user guides, online help and discussion forums on the Internet