The objective of Certbot, Let's Encrypt, and the ACME (Automated Certificate Management Environment) protocol is to make it possible to set up an HTTPS server and have it automatically obtain a browser-trusted certificate, without any human intervention. This is accomplished by running a certificate management agent on the web server.
This agent is used to:
- Automatically prove to the Let's Encrypt CA that you control the website
- Obtain a browser-trusted certificate and set it up on your web server
- Keep track of when your certificate is going to expire, and renew it
- Help you revoke the certificate if that ever becomes necessary.