Three main sources of applications software and their appropriateness.
Applications software consists of programs which carry out a specific activity task for the user.
The various sources of application programs are:
1. Application packages
These are also known as off the shelf programs and are ready made programs written by a manufacturer to perform a particular task which is common to many potential users and could be adopted by all of them. Packages may contain add-on facilities to allow for minor alterations required to suit certain businesses. Packages are normally appropriate in that:
i) The come with an assurance of system compatibility.
ii) They require minimum start up time and training cost during implementation.
iii) They can be tailored to meet certain unique needs.
iv) They can be sold to other users since they can use standard
2. Do-it-yourself programs
This application programs designed and developed by users themselves. They are also known as in-house programs and are normally not very complex. These programs are appropriate because: –
i) The invoice only a low cost since no specialists need to be hired.
ii) They are fast to develop and complete.
iii) They can be revised when need arises.
iv) They are a morale booster to electronic data processing staff.
v) They are naturally customised to the system being developed.
3. Specialist built or customised programs
These are application programs developed by software experts normally information analysts with experience in system analysis who are contracted by the organisation to develop an application program for its use. They are ideal where the program required is complex. These programs are appropriate in that:
i) The can be revised by the developer to suit changing demands.
ii) They are easy to learn and use.
iii) They are free from errors since they are thoroughly tested before being released as opposed to do-it-yourself programs.