Linux program to see what directories are taking up all the space?

[Cromulent]

I've used programs like this before on Windows 10 and wondered what programs are recommended to do this on Linux? I'm using OpenSUSE Tumbleweed and KDE on the btrfs file system, if that matters. I want to figure out why my install is 38GB in size, which seems somewhat excessive.

Thanks for any help.

 

[Cromulent]

KDE suit, Filelight. ?

Thanks. That was nice and easy to install and seems to do the job adequately.

 

[Cromulent]

ncdu its wonderful
https://youtu.be/6EYJA1ZWtw0?t=48
its an interactive Folder explorer its only 96K too. you can use ncdu -x to lock to folder/mount your inside

Thanks. I've just installed it. Will read the man page.