The calf muscles are comprised of two main muscles, the gastrocnemius which sits on top and the soleus that sits further underneath and goes down to your ankle. There are two primary angles to train your calves, standing calf raises which put more emphasis on gastrocnemius the seated calf raise which puts more emphasis on the soleus.

You should train both angles and make sure to train them correctly. Do not bounce up and down when performing these exercises. To correct this add a pause at the bottom and top of each movement to make the muscles do the work.