All microcontrollers have timers and counters as part of their architecture. The timer is a device that keeps track of how long a microcontroller has been performing a given task. It can also provide other time-related information that can be used to perform specific tasks. The counter is a device that serves as the basic unit of the timer. You can think of the timer as a watch, with the second hand being the counter. Each count advances the watch, indicating the overall duration of time that you’ve been observing the watch or an event.