Help understanding apt-src?

[sci-fi guy]

Could someone help me understand better what 'apt-src' is for and why one would want to use it?

[Partyboi2]

If the src lines are enabled it means that ubuntu will pull the source package from the repos, where as deb will pull the binary package from the repo's.

So if you have the src repo enabled you could download the source of a package with

apt-get source package which would download 3 files a .orig.tar.gz , .diff.gz and a .dsc

[sci-fi guy]

Does it automatically compile and install the package?
Is it interchangeable with apt-get?

[Partyboi2]

No it does not automatically compile and install the package. you would need to use other tools to do that..