r using renv to reproduce project, some library in renv.lock not in the folder /renv/library

Question

I was new in using renv

I noticed that there were many packages in the renv.lock but were not installed in renv/library folder, Is those library too basic and won't need to be installed?

For Example, here is the installed library list in renv/library

But There are several packages like MASS,Matrix which were listed in renv.lock 's json info, but they didn't show up in the folder list.