One could easily go without them but one should (IMHO) know the basics, for 2 reasons.
1) There may come a time where RegEx is the best solution to the problem at hand (see image below)
2) When you see a Regex in someone else's code it shouldn't be 100% mystical.
preg_match('/summarycount">.*?([,d]+)</div>.*?Reputation/s', $page, $rep);
This code is simple enough but if you don't know RegEx then that stuff thats in the first parameter may as well be a Martian language. The RegEx thats used here is actually pretty simple once you learn the basics, and to get you that far head over to http://www.regular-expressions.info/ they have ALOT of info about RegEx and its various implimentations on the different platforms/langauges they also have a great tutorial to get started with. After that check out RegexBuddy, it can help you build RegExs and while you build them if you watch what it does then it can help you lean, it by far was the best $39.95 I've ever spent.
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