(v) To make an object accessible. Whenever you access a file (that is, you edit a text file or run a program file), the operating system opens the file. Opening a file can be simple or complex depending on the operating system. For example, in a multiprocessing operating system, in which different users can share the same resources, the operating system must decide whether the file can be accessed simultaneously by more than one user, and if so, it must ensure that different users do not try to modify the file’s contents at the same time.
(adj) Accessible. When used to describe designs or architectures, open means public. See under open architecture.