What type of system is considered "outdated" or replaced by new technology?

The term "legacy system" refers to a type of computer system, application, or hardware that is outdated or no longer supported by the vendor. These systems often run on older technology that has been superseded by newer systems or software that are typically more efficient, secure, and capable of meeting modern requirements.

Legacy systems may still function adequately, but they may lack the features, interoperability, and support that contemporary solutions provide. Organizations sometimes continue to use them due to the high cost or complexity associated with migrating to new technology, but over time, the risk of relying on these outdated systems increases, including issues related to security and maintenance.

In contrast, operating systems are the software that manage computer hardware and software resources. Remote hosts refer to computers or servers accessed over a network, while compatibility systems often deal with ensuring software runs on different hardware or with different operating systems. These concepts do not inherently imply a system's obsolescence in the same way that legacy systems do.