The document discusses key concepts related to computer systems including: 1. It defines data, information, input, output, and processing. 2. It provides an overview of the basic components of a computer system including hardware, system software, and application software. 3. It explains bits and bytes as the basic units of digital information and discusses various numbering systems used in computing like binary, hexadecimal, and decimal.

1. 2.1.1
Overview of
Computer
System
2.1.2 Data
representation
Conversion
between binary
& hexadecimal
2.2.2
Hexadecimal
2.2.1 Binary
2.1.3 Storage
capacity

2. * Is data that has been processed
into meaningful form and is useful
to people
* Is collection of unprocessed items,
which can include text, numbers,
images, audio & video
* Eg: Nabihah can be reached at
011-33233510 (the data becomes
useful, it becomes information)
* Eg: The number 011-33233510
and name Nabihah are a pieces of
data (alone these pieces of data are
meaningless)

3. INPUT
Entering data into the
computer
OUTPUT
Data that has been
processed into a useful
form
PROCESS
Performing operation on the
data
STORAGE
Saving data, programs or output
for future

4. Computer System is:
A collection of related computer componwnts
(hardwares & software) that have been
designed to work together smoothly
The components of Computer:
Hardware
The components of a Computer: Software
System Software
Programs that
control/maintain the
operations of a
computer & its devices
Application Software
Programs designed to
make users more
productive

5. What is Bit?
The smallest unit of data a
computer can process consists of
1(on) or (off)
Usage
Use to measure data, transfer
rate of computer
communications devices
Usage
Use to measure storage
capacity
Size
The smallest unit of data a
computer can process that
consist of 0(off) or 1(on)
Size
8 bits grouped together as a
unit to store a single character
up to 256 individual characters
What is Byte?
8 bit groups together as a unit. A
byte provide enough different
combinations of 1s & 0s to
represent 256 individual characters

6. Refers to how
much disk
space
one/more
storage
Tape drive:
Few hundred
kilobytes to
several
kilobytes
Diskette: 1.44 MB
CD-ROM: 650MB-
700MB
Kilobyte: KB
Megabyte: MB
Gigabyte: GB Terabyte: TB

7. Numbering
system
concept
A number ing
system is a way
of representing
numbers
The decimal
numbering system is
the numbering system
is the numbering
system that represent
all numbers using
symbols
Common numbering
system used is calles
the decimal numbering
system/base 10
numbering system

8. Concept
# The
numbering
system that uses
16 different
symbols
(0,1,2,3,4,5,6,7,
8,9,A,B,C,D,E,F)
Why?
Hexadecimal notation is a
shorthand method for
representing the binary
digits stored in a computer
Example:
# 1100100110100001 –
can easily misread by
people
# Hexadecimal
notation groups digits
into units of four, which
in turn are represmted
by other symbols

9. Decimal to binary
(base 10 to base 2)
Binary to decimal
(base 2 to base 10)
Decimal to
Hexadecimal (base
10 to base 16)
Hexadecimal to
binary (base 16 to
base 2)
Binary to
hexadecimal (base
2 to base 16)
Hexadecimal to
decimal (base 16
to base 10)