Comment by ogogmad

Autodidact here. Beyond just the five core quantifiers

  .
  |
  ?
  *
  +

regex only has capture groups

  ()

and lazy variants of the core quantifiers "?", "*" and "+", which are helpfully called:

  ??
  *?
  +?

The rest is just shorthands.

So while I think it's a worthwhile suggestion not to show people the whole thing the first time round, I doubt that the whole thing is really that complicated.