Reading is fundamental, meaning the only general guide is to find or pick up the material, and read it. www.reddit.com. On my browser, I see a "Want to join?" link in the upper right corner. The "main page" has a search function.
Reddit is "like facebook" or "like twitter" in the sense that they are sites for open war between competing factions, with certain territories being occupied by one camp or the other. It takes some time and reading experience to figure out which side occupies which spaces.
Reddit is organized by subreddits (topics, groups) and then articles, and then posts. See subreddit "thedonald" for an example.
Thanks...that’s more than I knew.
The hierarchy of the database that is mysterious.