The "Ignore accidental trackpad input" trackpad option no longer appears in System Preferences. Functionality for "Ignore accidental trackpad input" is enabled automatically, by default for these computers.
Learn more
To determine if your Mac notebook has a multi-touch trackpad, please see Mac notebook: How to determine if your notebook has a Multi-Touch trackpad.
To learn about Macs with multi-touch trackpads and gestures, please see: