# Concepts The `epochs` module defines on-chain timers that execute at fixed time intervals. Other Mnova modules can then register logic to be executed at the timer ticks. We refer to the period in between two timer ticks as an "epoch". Every timer has a unique identifier, and every epoch will have a start time and an end time, where `end time = start time + timer interval`. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.metanovaverse.com/protocol-developers/modules/epochs/concepts.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.