1) Zaps are Nostr aware bitcoin payments, allowing you to tip, donate, get paid, and pay others for their content that you find valuable. Zaps have real world value. Zaps are better than likes. Likes ar hollow. Zaps for content are our super power here on Nostr.

2) I personally recommend to use a list of paid and public relays. Paid relays help to reduce spam, acting as a paywall. Free relays allow new users to easily find you. Relays aren't like Pokemon. You don't want to collect them all. The more you add, the more issues you'll have. Choose around a dozen or so. You'll want to choose relays that your friends are using. Otherwise you may not be able to find one another unless your client app that you're using is advanced and supports a new discovery method called gossip. Most don't right now, but will later this year.

https://nostr.watch has a list most of our relays.