Full text search uses TEXT indexes to quickly find all instances of a term (word) in a database without having to scan table rows.
TEXT indexes store positional information for terms in the indexed columns. Using a TEXT index to find rows that contain a term is faster than scanning every row in the table.
Full text search uses the CONTAINS search condition, which differs from searching using predicates such as LIKE, REGEXP, and SIMILAR TO, because the matching is term-based and not pattern-based.
String comparisons in full text search use all the normal collation settings for the database. For example, you configure the database to be case-insensitive, then full text searches are also case-insensitive.