Topics (pages) are free form content blocks. You can add them inside specified site or open them as independent page. Usually store owners use them to show policy pages, conditions of use, Frequently Asked Questions pages, tutorials. If you want to create custom page you need to go to Content Management -> Topics (pages).
Title - Name of your page
Body - Body of your new page
System Name - System name of your page
Password protected - Check if you want to create password protected site
Include in sitemap - Check if this page should be visible in sitemap
Include in top menu - Check if this page should be visible in top menu
Include in footer (column 1,2,3) - Check if this page should be visible in specified footer column.
Display order - Display order of this page
Accessible when store closed - Check if this page should be accessible when your store is closed
Topic template - Template of this page