Learn in the textbookPKI and the Core of Public Key Infrastructure
DefinitionA server certificate (サーバ証明書) is a certificate that shows a connecting browser or similar client that the destination, such as a web server, is genuine.
ExplanationBecause it is used in SSL/TLS (https connections), people also call it an SSL certificate. It contains the server's name and operator details, that server's public key and the signature of the issuing certificate authority.
AnalogyIt is like a notice at a shop's entrance in which a trusted third party confirms the shop's name and address. Customers can tell it is the real shop named on the sign, but not whether the shop has a good reputation.
Memory hook"Server" comes from serving: it is the certificate the side that answers requests uses to prove who it is.