A computer uses memory to store and process data. Primary memory, also called RAM, is faster but volatile, while secondary memory such as hard disks can permanently store large amounts of data but is slower to access. Different types of computer networks include local area networks (LANs) that connect devices within a building, metropolitan area networks (MANs) that span a city, and wide area networks (WANs) that connect multiple cities and countries over long distances.

2. A computer is basically an intelligent
machine when given proper instructions a
computer can understand what to do with
given accurate result. A computer helps
generate data. It can Store large amount of
data within a small sized hard disk. It can
process data. In addition, a computer
helps in retrieval and transmission of data
also.

3. Memory is very much like our brain as it is
used to store data and instructions. Computer
memory is the storage space where data is to
be processed, and instructions needed for
processing are stored. The memory is divided
into a large number of smaller portions called
the cell. Every cell/ location has a unique
address and a size.

4. Two types of memories are:
Primary Memory Secondary Memory
Primary memory is the main
memory of the computer system.
Accessing data from primary
memory is faster because it is an
internal memory of the computer.
The primary memory is most
volatile which means data in
primary memory does not exist if it
is not saved when a power failure
occurs.
Two types of Primary Memory are:
•RAM
•ROM
All secondary storage devices
which are capable of storing high
volume data is referred to
secondary memory. It's slower than
primary memory. However, it can
save a substantial amount of data,
in the range of gigabytes to
terabytes. This memory is also
called backup storage or mass
storage media.
Two types of magnetic disks are:
•Floppy disks
•Hard disks

5. Characteristic of Primary Memory
Primary memory is faster compares to secondary memory
It is a working memory of the computer
The computer can't run without primary memory
It is known as the main memory
You can lose data in case power is switched off

6. Characteristic Secondary Memory
Slower than primary memory
The machine can run without secondary memory
It helps store data in a computer
Secondary memory is known as a backup memory
These are magnetic and optical memories

7. Difference between LAN, MAN and WAN
LAN
Local Area Network
MAN
Metropolitan Area
Network
WAN
Wide Area Network
Use
Building, Office, School
And House
Multiple building or in
city
Multiple city country
Network Range
10-1000 M
5Km-50Km 100000000000 Km
Example
Internet Wi-Fi
Cable TV Network Internet