I'm a total newbie and don't know the terminology so let me describe what I'm looking for.
After you log in to WordPress, how does WordPress remember it's you as you browse around the website? Does it use a cookie? Or some other method of checking who you are?
Specifically, I'd like to make a NON-WordPress page that displays data from a database based on which WordPress user you are logged in as... if that is possible. Like if there were some way to "pass along" that you are WordPress user #223 (from the wp_users table) and then on my custom page I could then let you edit info in a different non-WP database that is associated with user #223. I'll ask on other message boards about how to code that part but that's why I first need to ask here if it's even possible to "pass along" what wordpress user number somebody is logged in as.