TechBro

[Lirange]

We use it in SQL Server. I don't really understand the differences between the SQLs (like I know there's also MySQL) but most of them are pretty similar I think.

Those are relational databases and SQL is how you access the data in those databases. Microsoft Access is another one. They're all fairly similar, though some functions may be named differently or even unavailable in certain databases. Syntax may differ a bit. But overall, if you know how to perform queries in one relational database, you know how to perform it on others.