Definition
JWE (JSON Web Encryption, RFC 7516) is the standard for encrypted JWTs — payloads encrypted (and optionally signed) so only the holder of the right key can read them.
In more depth
Where JWS provides integrity (signed but visible), JWE provides confidentiality (encrypted). The encrypted JWT serialization has five segments (header.encrypted_key.iv.ciphertext.tag) versus JWS's three (header.payload.signature).
JWEs are less common than JWS in real-world OAuth/OIDC because they add deployment complexity. They're used in some federation profiles and for high-sensitivity ID Token issuance.
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