The Stellar protocol allows you to map your public key (e.g. GCCVPYFOHY7ZB7557...) to an email-like address such as yourname*domain.com. This is called a 'Stellar address' (a la 'email address').

'Stellar addresses provide an easy way for users to share payment details by using a syntax that interoperates across different domains and providers.' - Stellar Developer Docs

Stellar addresses have two parts: a username and a domain. They are split by * instead of @.

For example - yoda*lumenauts.com:
+ yoda is the username,
+ lumenauts.com is the domain.

The username is limited to printable UTF-8 with whitespace and the following characters excluded: <*,>' - Stellar Developer Docs

When you send or someone else sends lumens to your primary account, the lumens can be sent to yourname*domain.com instead of typing in a long, error-prone string of random characters.

'Stellar client software to resolve email-like addresses such asname*yourdomain.com into account IDs like: 'GCCVPYFOHY7ZB75...' ' - Stellar Developer Docs