On the Pineco.de blog there's a tutorial posted introducing regular expressions and providing some examples and links to external resources/tools to help put them to use in your code.

Using Regular Expressions is not easy. Mostly we have the feeling we need to learn a new language on the top of those we already know. But, the power and the flexibility that RegEx provides, make it worthy to learn. Take a look at some useful patterns, tools, and sources!

The examples they provide show the matching all the words and matching all the content between specified tags. They end the post linking to several helpful tools including the Laracasts regular expression video and the regexr.com testing tool.