MSSQL is a suite of database software published by Microsoft and used extensively within our enterprise. Typically, it includes a relational database engine, which stores data in tables, columns and rows, Integration Services (SSIS), which is a data movement tool for importing, exporting and transforming data, Reporting Services (SSRS), which is used to create reports and serve reports to end users, and also Analysis Services (SSAS), which is a multidimensional database used to query data from the main database engine.
Azure SQL is a family of managed, secure, and intelligent products that use the SQL Server database engine in the Azure cloud.
SQL Server Management Studio (SSMS) is an integrated environment for managing any SQL infrastructure. Use SSMS to access, configure, manage, administer, and develop all components of SQL Server, Azure SQL Database, and Azure Synapse Analytics. SSMS provides a single comprehensive utility that combines a broad group of graphical tools with a number of rich script editors to provide access to SQL Server for developers and database administrators of all skill levels.
Transact-SQL (T-SQL) is Microsoft's and Sybase's proprietary extension to the SQL (Structured Query Language) used to interact with relational databases. T-SQL expands on the SQL standard to include procedural programming, local variables, various support functions for string processing, date processing, mathematics, etc. and changes to the DELETE and UPDATE statements.
Transact-SQL is central to using Microsoft SQL Server. All applications that communicate with an instance of SQL Server do so by sending Transact-SQL statements to the server, regardless of the user interface of the application.