IDENTIFY THE DIFFERENT TYPE OF USER INTERFACES

1) Command Interface

An interface that accepts types commands, 
one line at a time from the user
Contras with a menu – driven interface 
E.g.: MS-DOS , UNIX operating system

2) Menu Interface

An interface that accept instructions that user choose from menu of valid choice.
User often use mouse to point & click on the chosen instruction 
Contrast with a command-driven interface
E.g.: Windows 2000


3) Graphical User Interface

A user interface that allows the user to activate OS command by 
clicking on a desktop icon using pointing device such as mouse or touch screen.
GUIs evolved from command –driven user interface. 
User often use mouse to point & click on the chosen

4) Voice-Actuated Interface

Enables a user to use simple voice command to control physical environmental.
E.g.: The computer includes a voice card & associated voice recognition & training
software for interpreting & translating voice input into digital information readable 
by controller card for operating equipments @ control the environment.


5) Web-form Interface

Allow user to enter data that is send to a server for processing
Web form interface resembles paper  form because user need to fill out the form using web form elements

Basic Functions Perform by OS User Interface

Enable user to interact with the system
How to interact? By perform the user command interface /instructions from various types of interfaces.
Medium are used ; display screen, keyboard, mouse, light pen, the appearance of a desktop, illuminated characters or help messages.

1st GENERATIONS OF COMPUTER : VACUUM TUBES & PLUG BOARDS

1. Use of vacuum tubes
2. Big & Clumsy
3. High Electricity Consumption
4. Programming in Mechanical Language
5. Larger AC were needed

1st GENERATION

6. Lot of electricity failure occurred

2nd GENERATIONS OF COMPUTER : TRANSISTORS & BATCH SYSTEMS

2 nd GENERATION

1. Transistors were used
2. Core Memory was developed
3. Faster than First Generation computers
4. First Operating System was developed
5. Programming was in Machine Language & Assembly Language
6. Magnetic tapes & discs were used
7. Computers became smaller in size than the First Generation computers
8. Computers consumed less heat & consumed less electricity

3 rd GENERATIONS OF COMPUTER : ICs & MULTIPROGRAMMING :

3rd GENERATION

1. Integrated circuits developed
2. Power consumption was low
3. SSI & MSI Technology was used
4. High level languages were used

4 th GENERATIONS OF COMPUTER : PERSONAL COMPUTERS :

4th GENERATION

1. LSI & VLSI Technology used
2. Development of Portable Computers
3. RAID Technology of data storage
4. Used in virtual reality, multimedia, simulation
5. Computers started in use for Data Communication
6. Different types of memories with very high accessing speed & storage capacity

5 th GENERATIONS OF COMPUTER :

5th GENERATION

1. Used in parallel processing
2. Used superconductors
3. Used in speech recognition
4. Used in intelligent robots
5. Used in artificial intelligence

VARIOUS TYPES OF OS STRATEGY :

Batch Operating System
- This strategy involves reading a series of jobs (called a batch) into the
machine and then executing the programs for each job in the batch. This
approach does not allow users to interact with programs while they operate.

Multiprogramming Operating System
- The ability to do more than one job is called multiprogramming. The system
separates the memory out into several pieces and lets each one of the pieces
be a different job that the computer was running. The ability to do multiprogramming
 speed the computers up tremendously.
-  When one job idled to wait for input or output, the operating system could
automatically switch to another job that was ready.

Distributed Operating System
- An operating system that manages a group of independent computers and
                     makes them appear to be a single computer
- Distributed computations are carried out on more than one machine
- When computers in a group work in cooperation, they make a distributed
                       system.