Before you become a “domain connoisseur,” you need to understand the advantages of owning more then one domain and what you can do with them:
1) Redirects: Maybe when you registered your site there were other names you liked as well, or perhaps you registered the .net version of your name. It’s very easy to point these names to your existing site so when someone types in one of these alternate domain names in their browser, they’ll still wind up at your site.