What is meant by a task limited by I/O operations?

An I/O-bound task is a task whose performance mainly depends on the speed of input/output operations, such as reading or writing files, network requests, or database operations.

In such tasks, the processor often remains idle while waiting for I/O operations to complete. To improve efficiency, asynchronous programming or multithreading is often used so that other tasks can be performed during the I/O wait.

Example: downloading data from a remote server — the waiting time for the network response limits the overall speed of the task.