Operating System Services

Program execution – system capability to load a program into
memory and to run it
I/O operations – since user programs cannot execute I/O
operations directly, the operating system must provide some
means to perform I/O
File-system manipulation – program capability to read, write,
create, and delete files
Communications – exchange of information between processes
executing either on the same computer or on different systems
tied together by a network. Implemented via shared memory or
message passing
Error detection – ensure correct computing by detecting errors
in the CPU and memory hardware, in I/O devices, or in user
programs