Maybe you get a little seasick hearing about presets and samples. So I'll tell you the differences. Samples are sounds (mostly) in .wav format, which can be one shots or loops. These in turn can be drum samples, drum loops, bass loops, melody loops, one shot synths, etc. On the other hand, presets are presets made for various synths (such as Serum or Vital). These presets help a great deal as you can play more with the parameters they provide. Here you will find a wide variety of them so pay attention to which one best suits your needs.