A Certificate Authority (CA) is a trusted entity that issues digital certificates, which certify the ownership of a public key by the named subject of the certificate. This allows others (relying parties) to rely upon signatures or on assertions made about the private key that corresponds to the certified public key.
The global chain of trust depends on CAs. If a root CA is compromised, all certificates issued by it become untrustworthy. CAs validate the identity of entities requesting certificates, preventing attackers from successfully impersonating a valid domain.
We believe in automated, short-lived certificates. We leverage ACME providers (like Let's Encrypt) to rotate certificates frequently, reducing the blast radius of a key compromise. Manual certificate management is widely considered a malpractice.