SQL is the most commonly used programming language that requests and manipulates information from database management systems.
Functionality
With SQL, you can search regular and relational databases for specific information and manipulate the data they contain.
Relational databases are collections of tables filled with information that is somehow related. SQL searches those tables for a common thread (keyword) requested by a user and presents the search results in a table that includes only the requested data.
Level of Difficulty
At its core, SQL is a simple language. To use it, you must have a database created in software such as Microsoft Access, MySQL or SQL Server and Microsoft Notepad for code writing.