Programming languages used in most popular websites
        Websites      Front-end               Back-end                                     Database
                      (Client-side)           (Server-side)
        Google.com    JavaScript              C, C++, Go, Java, Python                     BigTable, MariaDB
        YouTube.com   Flash,HTML5, JavaScript C/C++, Python, Java, Go                      MySQL, BigTable
        Facebook.com  JavaScript              Hack, PHP, C++, Java, Python, Erlang, D, Xhp MySQL, HBase
        Yahoo         JavaScript              JavaScript, PHP                              MySQL, PostgreSQL
        Amazon.com    JavaScript              Java, C++, Perl
        Wikipedia.org JavaScript              PHP                                          MySQL, MariaDB
        Twitter.com   JavaScript              C++, Java, Scala, Ruby on Rails              MySQL
        Bing          JavaScript              ASP.NET                                      Microsoft SQL Server
        eBay.com      JavaScript              Java, JavaScript                             Oracle Database
        MSN.com       JavaScript              ASP.NET                                      Microsoft SQL Server
        Linkedin.com  JavaScript              Java, JavaScript, Scala                      Voldemort
                                    COMPUTER NETWORK
A computer network is a set of connected computers. Computers on a network are called nodes. The
connection between computers can be done via cabling, most commonly the Ethernet cable, or
wirelessly through radio waves.
The Internet itself can be considered as a computer network.
Types of Networks                                               Network Topology
The three basic types of networks include:                      The layout pattern of the interconnections
LAN, MAN and WAN.                                               between computers in a network is called
                                                                network topology. There are a number of
Local Area Network (LAN)                                        different types of network topologies, including
A network is said to be Local Area Network                      point-to-point, bus, star, ring, mesh, tree and
(LAN) if it is confined relatively to a small area.             hybrid.
It is generally limited to a building or a
                                                                    Point-to-point topology consists of a
geographical area, expanding not more than a
                                                                     direct link between two computers.
mile apart to other computers.
                                                                    Bus topology uses one main cable to which
Metropolitan Area Network (MAN)                                      all nodes are directly connected. The main
                                                                     cable acts as a backbone for the network.
Metropolitan Area Network (MAN) covers                               One of the computers in the network
larger geographic areas, such as cities. Often                       typically acts as the computer server.
used by local libraries and government agencies
                                                                    Star topology, each computer is connected
often to connect to citizens and private
                                                                     to a central hub using a point-to-point
industries.
                                                                     connection.
Wide Area Network (WAN)                                             Ring topology, the computers in the
                                                                     network are connected in a circular fashion,
Wide Area Networks (WANs) connect larger                             and the data travels in one direction.
geographic areas, such as London, the UK, or                        Mesh topology, every node has a direct
the world. In this type of network dedicated                         point-to-point connection to every other
transoceanic cabling or satellite uplinks may be                     node.
used.
                                                                    Tree topology combines multiple star
                                                                     topologies on to a bus.
                                                                    Hybrid topology is an integration of two or
                                                                     more different topologies to form a
                                                                     resultant topology.
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