computer hardware that arranges jobs to be done by the computer in an appropriate order
"The scheduler is a specialized piece of computer hardware designed to arrange incoming jobs so they are processed by the system in an efficient and logical sequence."
A person or device that determines a schedule, that determines the order that tasks are to be done.
"The project manager acted as a scheduler by carefully determining the exact order in which each team member would complete their assigned tasks."
In plain English: A scheduler is something that decides when different tasks should happen so everything runs on time without getting mixed up.
"The scheduler sent me an email to confirm my meeting time for tomorrow morning."
Usage: Use "scheduler" when referring to an automated system or software agent; reserve "scheduling" as a verb or noun for the act of arranging times. Avoid using it interchangeably with "planner," which implies human agency and broader strategic organization rather than strict temporal sequencing.
The word scheduler comes from adding the suffix "-er" to schedule. It was formed to describe a person or thing that creates or follows a schedule.