1. Human–computer interfaces

2. Operating systems are software (i.e. programs)
used to control the hardware directly
used to run the applications software
Is a software/program that controls/runs the computer system

3. Functions of operating systems 1
Manage and control devices.
Provide a user interface.
Hide the complexity of hardware from user.
Deal with errors.
Provide interface between applications software and hardware.
Features or functions:-
Provides a user interface so hides away or the programming.
Deals with errors
It boots up and shuts down the computer
Controls hardware
Enables software to run on the computer. It runs it, runs the application

4. Functions of operating systems 2
Allow installation of new hardware and software.
Utilities for virus scanning, encryption, etc.
Handle the storage of data.
Maximize memory use.
Automatically recognize new hardware.
Organize resources when tasks are being worked on simultaneously.

5. Types of user interface
graphical user interface (GUI)
command line
menu/dialogue boxes
touch sensitive
voice driven
biometric
Windows XP, Windows Vista, Apple OSX and Ubuntu all have graphical user interfaces.

7. TYPE OF INTERFACE
ADVANTAGES
DISADVANTAGES
GUI
Intuitive/easy to use.
Easy for disabled users.
No need to learn lots of commands.
Not complete control as with a command line interface.
Only click on what is there already.
COMMAND LINE
Needs less memory to run than a GUI or other interfaces.
Less processing power needed compared to others.
It can take a long time to type commands.
User must learn how to write commands.
VOICE RECOGNITION
Speech is faster than typing.
Helps people with certain disabilities.
Don’t need to learn to type.
In a noisy room it can’t understand you.
Heavy accents are hard to understand.
Need to be close to microphone.
MENU
Everything is in a logical order.
BIOMETRIC
Good security: can’t ‘forge’ a fingerprint.
Can’t lose or share your finger (print).
Replaces need for complicated passwords that can be forgotten.
Expensive to set up.
Have to train users.
TOUCH SCREEN
No need for keyboard & separate monitor.
Good for areas of high public use as more durable and easier to clean. 
Can lose sensitivity and get damaged.
More expensive than interfaces on a computer (GUI, etc.)