The difference is that a pidgin is a temporary, makeshift language to facilitate communication between peoples who speak different languages natively, whereas a creole is a language that people actually live in. The word "pidgin", though, often gets attached to a temporary patois and remains attached even after the language progresses to a creole. Sometimes a pidgin will hang around even after the conditions that created it have gone away. The South Seas English pidgin hung around as a regional lingua franca for a long time, partly because it was handy even when not dealing with English speakers, and partly because it was a mark of distinction among the people that the English in Australia had exploited. Eventually, though, it did creolize -- Tok Pisin came from that pidgin, but it is not a pidgin any longer.

Hawaaiian Creole English (the academic name for the language) is still generally referred to by its speakers as "Pidgin", even though the progression from pidgin to creole was documented almost as soon as the first plantation immigrants had kids old enough to talk. (Many African creoles are similarly still called "Pidgin" by their speakers, even though the language is not a pidgin per se.) The parents of those children spoke a pidgin; the words were mostly English (with the odd word drawn from Japanese or one of the Philippine languages by concensus), but the grammar was extremely simplified and the structure (head-first, head-final, etc.) tended to reflect the speaker's native tongue.

You can trade and get work done in a pidgin, but you can't communicate with much subtlety, and the kids needed something they could chat in. The kids (all young children are linguistic geniuses compared to us older folk) quickly developed grammar that was consistent and had rules. You could speak the language well, or speak it badly.

It's difficult to make a grammatical error in a pidgin; errors are mostly about vocabulary. A creole, on the other hand, is a real language. You can get all of the words right, but still make mistakes -- mistakes of the sort that the yellow big ball would be in English. Dey bin stay buy in Hawaaiian Creole is "they were buying" ("bin" puts it into the past tense and "stay" makes it continuous/progressive); dey stay bin buy is gibberish (it would mean something like "they are still finished buying").

I agree, it's a bit confusing.