Basic authentication is the simplest authentication scheme, which is built into the HTTP protocol. To use it, the client needs to send HTTP requests with the authentication header, which contains the word Basic followed by a space. Then, the given string of username and password will be considered as username/password and encoded into Base64. For example, if the username and password are Sunnat629 and pa$$worD, these will be converted into Base64 encoding, which will be U3VubmF0NjI5L3BhcyQkd29yRA== as authorized. Finally, the client will send Authorization: Basic U3VubmF0NjI5L3BhcyQkd29yRA== to the server.
Base64 can easily be decoded. This is neither encrypted nor hashed. If you want to use the basic authentication, we highly recommend using this together with other security tools, such as HTTPS/SSL.