Social engineering attack: This is a type of attack that relies on tricking the victim into clicking on a malicious link or opening an attachment. In this case, the concealed URL in the email is likely a malicious link that will lead the victim to a website that is controlled by the attacker. Once the victim clicks on the link, the attacker can then install malware on the victim's computer or steal their personal information.
Obfuscated links: This is a technique used to hide the true destination of a link. This can be done by using a variety of methods, such as using shortened URLs or encoding the URL in a way that makes it difficult to read. In this case, the concealed URL in the email is likely obfuscated, which makes it more difficult for the victim to identify as malicious.