The Properties button gives you the ability to easily edit the page's information. Clicking it presents a window with several tabs:

• On the Standard Properties tab, you can edit your page's name, description, time stamp, and owner:

The Page Name is used in Navigations and in the Title tag of your page. 
The Description is used by some blocks like the Page List block for navigations. Some themes will also use the Description as a Meta Description field if you don't put something in the custom attribute (see below)
The Time Stamp is just when the page was made. It is used for navigations that sort pages by date created. If you're looking to do a timed page release, you need to investigate advanced permissions. 
The owner is generally not used a lot in concrete5 by default, and doesn't generally have any impact on permissions. Some of the add-ons make use of it for Authored by lines. 

• Page Paths and Location allows you to control what your page's URL looks like in your browser's address bar:

You can add Additional Page URLs for 301 redirects. Each URL starts at your site's root. So type /directory/file if you want the page to show up at mysite.com/directory/file (include that leading slash). Don't forget to hit save here for your changes to take effect. 

• Custom Attributes allows you to give your page special characteristics, including meta information, tags, and other characteristics (what appears here will depend on how your site is set up with Page Types and Page Attributes):

Some custom attributes are geared for simple meta data, some are more programatic in nature (like Exclude from Nav). Here's a list of some commonly used custom attributes.

• Speed Settings lets you control how the page you're editing is treated by concrete5's caching system. This only shows up if you've got caching turned on in your dashboard. If a particular page on your website is receiving large amounts of traffic, or has specialised functionality which conflicts with the cache settings that the rest of your website uses, you can tweak the cache settings for that page here.