EDIT: Forget the commas. I can do with spaces. But how do I retreive all the words that are in one string? I don't understand how the getWords() function works...
getWord(%string,0) gets the first index (0) word in a string. So index 0 is the first word, 1 the second etc. getWordCount(%string) returns the amount of words in a string. So something like getWordCount("I like to eat fish") will return 5. getWord("I like to eat fish",2) will return "to".
To get all the words in a list, just do a for loop using getWordCount as the conditional (something like: for(%i=0;%i<getWordCount(%string);%i++)) you can also look in RTB (server control I believe) which has some neat word list functions you could use.