It is a content server, that connects you to other Nostr users. Basically it stores the text, images, videos etc. Relays makes the Nostr protocol strong because you as a user can connect to as many relays you desire, or install your own; which means you can upload whatever you want, nobody can sensor you.

🖥️ 🛜 🆓 🗣️

#plebchain

#nostr

#relays