the Split function is to split for example given this string "abc,def;123" with the regex [,;] where result string array is then ['abc','def','123']
And ExtractAll is like MatchAll, just with the difference, that ExtractAll returns the extracted strings of the found match capture groups, instead Start/Length integer pairs, i.e.
[[whole-match-string of the first whole match, first-capture-group-string, second-capture-group-string, ...],
[whole-match-string of the second whole match, first-capture-group-string, second-capture-group-string, ...],
[whole-match-string of the third whole match, first-capture-group-string, second-capture-group-string, ...],
...
]