The seams that are created when drywall panels are installed must be filled with 'joint compound' (or 'spackle, mud, compound,) and seam tape (paper or fiberglass) in order to produce a smooth flat surface. As far as there being or using specific types of compound for filling nail dimples and seams, you should use joint compound for both. Joint compound when it has set produces the hardest and strongest seam. Three layers of compound each applied wider than the other are the norm. If you want a highly smooth finish with no marks at all you can use a 'light weight' joint compound as a final or fourth coat. When dry it has a slight yellow tint that easily sands with a high grit paper. If the job needs to progress quickly, I will sometimes set the tape in a bed of mud, pressing it tightly to the surface and rather than wait for it do dry overnight will immediately cover it with a 6-8 inch wide layer of compound. Next day knock off any burrs or ridges and apply the second 10-12 inch layer, etc.