docs: update explanation of setImmediate vs setTimeout

[sebastiendan]

Description

Clarifies the execution order of setTimeout and setImmediate when called from the main module and inside an I/O callback.

The current they will be both run in the next iteration of the event loop phrasing is confusing without the explicit context of where the code is run (main module vs I/O callback).

Check List

• I have read the Contributing Guidelines and made commit messages that follow the guideline.
• I have run pnpm format to ensure the code follows the style guide.
• I have run pnpm test to check if all tests are passing.
• I have run pnpm build to check if the website builds without errors.
• I've covered new added functionality with unit tests if necessary.

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Project	Deployment	Actions	Updated (UTC)
nodejs-org	Ready	Preview	Feb 13, 2026 5:55am

[github-actions]

👋 Codeowner Review Request

The following codeowners have been identified for the changed files:

Team reviewers: @nodejs/nodejs-website

Please review the changes when you have a chance. Thank you! 🙏

[Copilot]

Pull request overview

This PR updates the documentation for setImmediate() to clarify the execution order differences between setTimeout() and setImmediate() in different contexts (main module vs I/O callbacks). The change addresses a confusing statement about when these functions execute in the event loop.

Changes:

• Clarified that when called from the main module, both setTimeout(0) and setImmediate() run in the next iteration of the event loop
• Added explanation that when scheduled inside an I/O callback, setImmediate executes in the current iteration's check phase while setTimeout must wait for the subsequent iteration's timers phase

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

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[AugustinMauroy]

cc @nodejs/timers