A computer is a programmable device that can store, retrieve, and process data using its central processing unit (CPU) and memory. An operating system manages the computer's activities and resources. There are different types of programming languages at different levels of abstraction from the hardware, including machine language, assembly language, procedural languages, and object-oriented languages. Event handling in programming allows a program to respond to user interactions like button clicks through listener interfaces.

3. Computer:
• A programmable device that can store, retrieve, and process data.
Bus
Storage
Devices
e.g., Disk, CD,
and Tape
Memory
CPU
Communication
Devices
Input
Devices
Output
Devices
e.g., Modem,
and NIC
e.g., Keyboard,
Mouse
e.g., Monitor,
Printer

4. The operating system is a program that manages and controls a computer’s activities. The popular
operating systems for general-purpose computers are Microsoft Windows, Mac OS, and Linux.
User
Application Programs
Operating System
Hardware

5. Computer program:
• A sequence of instructions to be performed by a computer.
Computer programming:
•Problem-Solving Phase
•Implementation Phase
•Maintenance Phase
Algorithm: A step-by-step procedure for solving a problem in a finite amount
of time.
Programming language:
• A set of rules, symbols, and special words used to construct a computer program
Steps in learning language:
Alphabets
Digits
Special Symbols
Characters
Variables
Keywords
Instructions
Program

6. ASSEMBLY
LANGUAGE
PROCEDURE
- ORIENTED
OBJECT ORIENTED
PROGRAMMING
MACHINE LANGUAGE
HARDWARE

7. MACHINE LANGUAGE The language, made up of binary-coded instructions, that is
used directly by the computer.
A low-level programming language in which a mnemonic (Assisting
ASSEMBLY LANGUAGE
in memory) is used to represent each of the machine language instructions for a particular
computer.
Assembly Language
Machine Language
ADD
100101
SUB
010011
Assembler: A program that translates an assembly language program into machine code.
Compiler: A program that translates a high-level language into machine code.
Machine Code
Assembly Source
Assembler
ADDF3 R1, R2,R3
1100101010011010

8. EVENT HANDLING: Event handling comes with
user defined GUI. For example when you click
on a button, it is supposed to be an event. and
the way the java handles these events is termed
to be EVENT HANDLING. For this event handling
you have listeners..who listen to your specific
actions..i.e...clicks, press, release etc..
for more reference see this
http://java.sun.com/j2se/1.4.2/docs/api/java/a
wt/event/package-summary.html