OS X is a series of Unix-based graphical interface operating systems developed and marketed by Apple Inc. It is designed to run on Macintosh computers, having been pre-installed on all Macs since 2002. It was the successor to Mac OS 9, released in 1999, the final release of the “classic” Mac OS, which had been Apple’s primary operating system since 1984. The first version released was Mac OS X Server 1.0 in 1999, and a desktop version, Mac OS X v10.0 “Cheetah” followed on March 24, 2001. Previous releases of OS X were named after big cats; for example, OS X v10.8 was referred to as “Mountain Lion”. However, with the announcement of OS X Mavericks in June 2013, this was dropped in favor of Californian landmarks. Within the market of desktop, laptop and home computers, and by web usage, OS X is the second most widely used OS after Windows.
securityd — Security context daemon for Authorization and cryptographic
securityd maintains security contexts and arbitrates cryptographic opera-
tions and Security Authorizations. Access to keychain items is routed
through securityd to enforce access controls and to keep private keys out
of user process address space. Authorization calls also communicate with
securityd to enforce rules contained in the /etc/authorization database.
All user interaction with securityd is mediated through the Security
This command is not intended to be invoked directly.
securityd was first introduced in Mac OS X version 10.0 (Cheetah) as the
“Security Server” and was renamed in 10.4 (Panther).