I'm trying to delete all unnecesary programs from my computer and SQL makes me doubt. I don't use it directly, but can't recall any program using it. Is it safe uninstalling?
Have you installed Visual Studio on this machine? It's one of the default components.
Otherwise, most (but not all) applications use SQL Server Embedded instead, which doesn't install extra programs.
If you're not sure about uninstalling it, you can disable the SQL Server services in Administrative Tools...Services, use the laptop for a little while and see if any errors pop up.
In any case it's never "unsafe" to uninstall. Worst case you'll need to reinstall one of your applications.
There's very few needs for SQL Server for a home computer, and if you do need it for a program, that program should tell you when you try to run it, so in 99% of existing cases, it is safe to remove. Just keep the databases backed up if the uninstaller asks you.