7.3.5. Self-signing your key

You should self-sign your key after you've finished changing its properties and are happy with it. Self-signing ensures that nobody can tamper with the properties of your public key.
To self-sign your key, click on your key and choose Edit → Sign Key from Key Management, or click the Sign Key button from Key Properties.

You may also sign other people's public keys in order to build a Web of Trust, although this is not required for basic Enigmail operations. This will be explained in Section 7.7.1.