hold the value of captured groups. In some regex implementations there are only nine of them, however, with most contemporary Javascript implementations you can have up to 99 such capture-groups ...

As developers use JavaScript ... is that if you need access to the details of where groups are matched within a string, you can now use the regex match indices feature to get it.

You can define parts of your regex that are meant to be broken out as their own captured elements. For this we use parentheses, (), to indicate capture groups. For instance, if we say data:([0-9 ...