Socket Programming Question:

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Using IP addresses to access hosts on a network is fine for the IP software. Most people are more comfortable with names, and procedures for both proper name construction and translation of these names into IP addresses has been in existence for some time. The most commonly used is the Domain Name System (DNS), occasionally but inaccurately referred to as the Domain Name Service. Naming in DNS is done hierarchically, that is, in a tree-structure format, much like the UNIX file system naming. The top two levels are controlled by the Internet Network Information Center (NIC) at SRI International.
At the top of the domain are two-letter country designators and three-letter (usually) general category designators within the USA. Some examples are:

* fr -- France
* gov -- government
* nz -- New Zealand
* com -- commercial business
* us -- USA
* edu -- educational institution
* uk -- United Kingdom
* mil -- military

The next level usually identifies the institution. For example:

* ibm -- IBM Corporation
* utdallas -- UT-D
* ti -- Texas Instruments (TI)
* nasa -- NASA

DNS and other software help in maintenance of these naming conventions and in the translation of host names to IP addresses and vice versa.