Command-line interface

Advantages of command-line interface:

Disadvantages of command-line interfaces:

Menu driven interface:

Advantages of menu driven interface:

Disadvantages of menu driven interface:

Graphical user interface (GUI)

Advantages of GUI

Disadvantages of GUI:

Voice interface:

Advantages of voice Interfaces:

Disadvantages of voice interfaces:

Special devices:

Advantages of touch sensitive interfaces:

Disadvantage of touch sensitive interfaces:

In older versions of Microsoft office, there was an Office Assistant which popped up to give context-sensitive help. After a while this could become annoying and it was often turned off.

Point of sale interface:

Biometric Systems:

2 types of software:
Applications software: programs that perform a specific task (e.g. stock control program or computer game) and generic programs that can be used for general-purpose tasks (e.g. a word-processing program).

The computer is designed with a small amount of software on a ROM chip, which allows the computer to find the main part of the operating system on the hard drive. This process is called booting.

Single-program:
Batch- Processing systems:.

The advantages of batch-processing is that processing can be done off peak-times. Also, no human intervention is required once the batch has been started.

Multi-access Systems:

There is no computer unit because they are connected to the mainframe computer. However, networks are starting to replace the mainframe computer.

In a distributed system, the processing and resources are shared between a number of different computers. It is the operating system that has to make sure that each of the computers in the system communicates properly.

Real-time systems:

Another example of a real-time system is a flight simulator used to train pilots.
Real-time operating systems can be found in embedded computers. The operating system is stored in a ROM chip and runs and manages a single program that operates such as a washing machine or a digital camera.

Parallel- Processing Systems:

Special programming languages have been developed to write applications for parallel-processing systems and complex operating systems are needed to share out the tasks to the processors and coordinate their activities.

Interactive Systems:

System Security:

Single-user security involves protecting files of data from accidental change or deletion and there is less need for protection from unauthorised users than there is on a multi-user system or network.

The time and date when a file was last changed are recorded. This means if a file has been deliberately changed, it may be possible to track down who was using the computer at the time. The attribute of a file can be set to “read-only”. This would make it impossible to accidentally change or delete an important file.

Other software may be installed which protects the files on a computer from being changed by viruses. In practice, a combination of security measures needs to be in place.