The Lightweight Directory Access Protocol (LDAP) is a  protocol that is used for querying and modifying directory services running over TCP/IP.

You know that a directory is a set of objects with attributes organized in a logical and hierarchical manner.  We can take the example of a simple telephone directory, which consists of a list of names of persons or organizations organized alphabetically, with each name having an address and phone number associated with it.

We can usee the LDAP directory tree to reflect various political, geographic, and/or organizational boundaries, depending on which model we have chosen. Now-a-days mostly in the Linux networking, we are using LDAP for various purposes Domain name system (DNS) names for structuring the topmost levels of the hierarchy. Deeper inside the directory might appear entries representing people, organizational units, printers, documents, groups of people or anything else that represents a given tree entry (or multiple entries).