When you think of iTunes, Apple’s hugely successful online media store — it recently surpassed Best Buy and Target in music sales and is predicted to overtake Wal-Mart this year — it’s generally because you want to download the song of your choice for 99 cents or an entire album, television show, movie or audio book to your home computer. But you may not know about iTunes Essentials, a corner of the site where Apple’s music geeks compile set upon set of playlists to educate and enrich you, musically speaking. We’re not talking about just the obvious stuff. The Basics are there, of course, defined as “the biggest, best, and most important songs” of an artist, era, or genre. After that comes Next Steps, “when you’re ready to move beyond the hits.” If you’re the precocious type, you can skip ahead to Deep Cuts, where you’ll find the “criminally ignored” and “unjustly under-appreciated.” So, say you’ve started dating someone who loves ’90s Alt Rock, a genre you know nothing about. For a mere $24.75, you can own 25 of the Basics — like Jeremy by Pearl Jam (pictured) and Beck’s Loser to memorize and leave playing when your new pal comes over (you can buy single cuts for 99 cents each). At Next Steps, you can impress him or her by purchasing Mazzy Star’s Fade Into You, and if the relationship takes off, Deep Cuts has Sonic Youth’s Kool Thing and 24 others. Buy the complete set of 75 songs for your wedding; it’s only $74.25. The tunes are broken down into three sections: Artist Essentials, Genre and History (like ’90s Alt Rock) and My Groove, which includes movie hits, dance music and everything that won’t fit in the other two categories — I (heart) NY anyone? Tired of being the outsider when the “hip” people at the office start talking about music? Do some homework. Expand your tastes. Join the conversation.