1.1 approaches to system development

Question 1

What is a system

Answer 1

A system is a set of processes

It systems use computer technology to complete a task

Question 2

What is systems development

Answer 2

It is the methodology that is used when creating software
- software developers create new applications using code.
- they can pick different methods of software development- waterfall, rapid application development, agile.
Applications are developed either- from scratch, to replace paper based system- to replace and existing piece of software.

Question 3

The software crisis

Answer 3

Term originated in the 1960s when computer hardware RAM CPU speed etc began growing much faster than the ability of software developers to actually make effective use of these new capabilities.

Question 4

Cause of the software crisis

Answer 4

The machines have become several orders of magnitude more powerful!
- as long as there were no machines, programming was no problem at all. When we had a few weak computers, programming became a mild problem, and now we have gigantic computers, programming has become an equally gigantic problem.

Question 5

What did the software crisis result in

Answer 5

Resulted in software that was 
low quality, 
did not meet users needs, 
was not delivered on time and 
was not within budget. 

Updating old software also became a problem and this has continued ever since.

Question 6

The need for software systems.

Answer 6

Individuals and organisations need SW to meet their needs. There are two ways to get SW.

off the shelf
Tailor made.

Question 7

Off the shelf

Answer 7

Many buy same generic package. Ranges from productivity tools like MS office to specific SW for a common task. Eg. Payroll or accounting.

Sometimes these generic packages can be tweaked to suit each business eg. Use ur own templates in office.

Question 8

Tailor made AKA bespoke.

Answer 8

Tailor Made

Your company uses a SW developer to create unique SW package just for ur specific needs.

Question 9

Advantages of off the shelf

Answer 9

Meets general needs
Short developed time
Low cost

Question 10

Disadvantages of off the shelf

Answer 10

Cannot meet all needs

Not developed enough

Question 11

Tailor made advantages

Answer 11

Can meet all needs.
Do what needed to do.
Developed well

Question 12

Factors affecting system development

Answer 12

• the requirements of the business may have changed.
• company expanded
• current system inflexible
• can’t get technical support- expensive
• advances in hardware and software

Question 13

What does a computer system consist of?

Answer 13

User interface
Processes
Data

Question 14

User interface

Answer 14

Allows the user to input data.

Shows the outputs after that data has been processed.

Question 15

Processes

Answer 15

Raw facts and figures are processed to create useful information.

Question 16

Data

Answer 16

User inputs- the desired temperature on an air conditioning or central heating unit.
- the time for an alarm to go off on a phone.

Senor inputs.
Large amounts of raw data from other systems.
- the examination results of every pupil in a school.

Question 17

Systems Analyst

Answer 17

• analyse the data processing requirements of the organisation.
• produce a data processing requirements documentation that other member of the team will use.
• conduct feasibility study. a report which will determine whether or not user needs can be met.
• produce the systems specification. a detailed list of what the new system will contain. how it will be tested to make sure it meets set criteria. how the system will be implemented.
• deal with any problem that occur during the testing of the system.

Question 18

Project manager

Answer 18

• to schedule the project
• split the project into specific tasks and sub tasks
• to allocate resources
• to identify and respond to risk or bottlenecks
• monitor the progress of the project
• to report back to clients as the project progresses.

Question 19

Programmer

Answer 19

• responsible for writing the source code. Using a programming language such as Visual Basic. Written from the module specifications.
• develop a test plan and test the program.
  Testing is usually not done by the programmer but instead by an independent software tester.
• debug the program. Correct any faults found during testing.
• produce technical documentation. Notes about the code used l, how and why the programme was put together that way. Will be used during the maintenance stage.