A set of software that provides the infrastructure for a computer. The stacks differ whether installed in a client or a server. Clients - OS and Related Utilities The technology stack in a client machine includes the operating system and related support programs and all runtime environments necessary to support the applications, such as Java (see Java Virtual Machine). The stack may include the applications, although that is generally considered a separate "application stack." The word "technology" implies system software, not application software. See application stack. Servers Employ Services For servers, the stack includes all the programs mentioned for the clients with the addition of database software and support for several programming languages. If Web based, whether public or private, a variety of server software is included, such as Web server, mail server, FTP server and other "services" software. See LAMP.