Instant pot is a brand of electric pressure cooker, however, it has 6 additional (or 5 additional if you buy the 6in1) features in it. The pressure cooker part is just 1 of the features, although the main selling point of it.
Also from what I understand the Instant Pot implemented additional safety measures that previous pressure cookers did not. But I truly don't know any details about what those are or if they really are more safe than other brands or if it's a sales gimmick.