The Internet, as a “network of networks”, consists of many computers, called servers or hosts, which are linked by communication lines. The administrators of these hosts may make information or software stored on them publically available, so that others can view, download or use the data. At the last count , there were an estimated 4.9 Billion people connected to the Internet.
[1] In fact, the distinction between clients and servers is becoming very blurred, with the advent of peer-to-peer software, personal web servers and other new uses.