about it

1. YOUSUF 10 AB

2.  s a telecommunications network which
allows computers to exchange data. In
computer networks, networked computing
devices pass data to each other along data
connections (network links). Data is
transferred in the form of packets. The
connections between nodes are established
using either cable media or wireless media.
The best-known computer network is
the Internet.

3.  devices that originate, route and terminate the
data are called network nodes.[1] Nodes can
include hosts such aspersonal
computers, phones, servers as well as networking
hardware. Two such devices are said to be
networked together when one device is able to
exchange information with the other device,
whether or not they have a direct connection to
each other.
 Computer networks differ in the transmission
media used to carry their signals,
the communications protocols to organize
network traffic, the network's size

4.  Computer networking may be considered a branch
of electrical engineering, telecommunications, computer
science, information technology or computer engineering,
since it relies upon the theoretical and practical
application of the related disciplines.
 A computer network facilitates interpersonal
communications allowing people to communicate
efficiently and easily via email, instant messaging, chat
rooms, telephone, video telephone calls, and video
conferencing. Providing access to information on shared
storage devices is an important feature of many networks.
A network allows sharing of files, data, and other types of
information giving authorized users the ability to access
information stored on other computers on the network. A
network allows sharing of network and computing
resources.

5.  Computer communication links that do not support
packets, such as traditional point-to-point
telecommunication links, simply transmit data as a bit
stream. However, most information in computer
networks is carried in packets. A network packet is a
formatted unit of data (a list of bits or bytes, usually a
few tens of bytes to a few kilobytes long) carried by
a packet-switched network.
 In packet networks, the data is formatted into packets
that are sent through the network to their destination.
Once the packets arrive they are reassembled into their
original message. With packets, the bandwidth of the
transmission medium can be better shared among
users than i

6.  The physical layout of a network is usually less
important than the topology that connects
network nodes. Most diagrams that describe a
physical network are therefore topological,
rather than geographic. The symbols on these
diagrams usually denote network links and
network nodes

7.  A local-area network (LAN) is
a computer network that spans a relatively
small area. Most LANs are confined to a single
building or group of buildings, however

8.  Network security[1] consists of the provisions
and policies adopted by a network
administrator to prevent and
monitor unauthorizedaccess, misuse,
modification, or denial of a computer
network and network-accessible resources.
Network security involves the authorization of
access to data in a network

9.  Network security starts with authenticating,
commonly with a username and a password.
Since this requires just one detail
authenticating the user name —i.e. the
password— this is sometimes termed one-
factor authentication. With two-factor
authentication, something the user 'has' is also
used (e.g. a security token or 'dongle', an ATM
card, or a mobile phone); and with three-factor
authentication, something the user 'is' is also
used (e.g. a fingerprint or retinal scan)

10.  Wi-Fi (or, incorrectly but commonly, WiFi) is
a local area wireless technology that allows an
electronic device to participate in computer
networking using 2.4 GHz UHF and
5 GHz SHF ISM radio bands.
 The Wi-Fi Alliance defines Wi-Fi as any "wireless
local area network" (WLAN) product based on
the Institute of Electrical and Electronics Engineers'
(IEEE) 802.11 standards".[1] However, the term "Wi-
Fi" is used in general English as a synonym for
"WLAN" since most modern WLANs are based on
these standard