* Learned a regular expression is of type Regexp
* Learned one can match a sting by following the string with a Regexp
* Learned the matching string is returned
*   or nil is returned if not matched
* Learned about optional (?) and one-or-more (+) and zero-or-more (*) patterns

[#65851512]
* Learned first match from the left is taken when matching
* Learned character classes are given inside []
* Learned \d is shorthand for any number
* Learned [] can include ranges of characters, like [a-z]
* Learned \s is shorthand for any whitespace characters

[#65851512]
* Learned \w is shorthand for [a-zA-Z0-9_]  (the underline was new)
* Learned . is shorthand for any character EXCEPT \n
* Learned character classes can be negated by starting with ^ e.g. [^a-z]
* Learned shorthanded character classes can be negated by using the capital letter version
* Learned \A anchors the begining of  the string (that WAS new)
* Learned \z anchors the end of the string (that WAS new)

[#65851512]
* Learned '^' anchors pattern to the start of lines
* Learned '$' anchors pattern to the end of lines
* Learned \b anchors pattern to a word boundary
* Learned () can be used to group things together
* Learned () captures groups by number
* Learned $1, $2, etc., can be used to access the captures in ()

[#65851512]
* Learned (xxx|yyy|zzz) using the verticle pipe or the options
* Learned .scan can be used to "find all"
* Learned .sub can be used to "replace"
* Learned .gsub can be used to "replace-all"

[#65851512]