Definition - What does Indexing mean?
In general, indexing refers to the organization of data according to a specific schema or plan. In IT, the term has various similar uses including, among other things, making information more presentable and accessible.
Techopedia explains Indexing
One example of indexing is the legacy Microsoft Indexing Service, which maintained an index of files on a computer or in an operating system environment. Another example is database indexing, which involves creating an index for a database structure to help expedite retrieval of data.
One common type of indexing in IT is called "search engine indexing." Here, IT tools aggregate and interpret search engine data, again, to streamline data retrieval. This type of indexing is also sometimes called Web indexing. IT experts explain that indexing helps to make searches less labor intensive — without an index, the search engine would have to search every document at its disposal equally, whereas with an index, much of this work is eliminated.