What is the purpose of the page URL?
This setting on the page form will control what search engines see, and what your page link looks like.
The link to your page depends on what it is attached to. Typically, the page links will look something like this:
Note: Duplicate page names are not allowed. Once you "grab" a page URL, it is yours forever.
Recommendation for Public Lists:
The URL name should make it very obvious to search engines what it is related to. For example, eventida.com/BigBash#bb_tickets will likely show up when someone searches "admission to Big Bash.