it indicates they are using an identity verification service.

but identity doesn’t work the same way in nostr. nostr doesnt verify a person’s real world identity. its more a way to verify this Diyana is actually this Diyana and not another diyana.

this is handled by something called NIP 5. NIPs are just bits of code in nostr that do specific things. Like a bicep pulls your arm toward you, or your quadriceps extends your leg. Different NIPs have different jobs.

NIP5 is the bit of code dedicated to the particular job of verification. So if you see someone mention “NIP 05”, this is what it refers to.

Some more tech savvy people use their own website for verification, but there are NIP 05 services that are much more simple.

This page explains this more, and has a list of free verification services: