Reminders is the to do list manager that Apple includes with OS X. You can use it to create as many to do lists as you need, for whatever reason. Reminders enables you to set due dates for specific items, with alerts so you'll be reminded as the date approaches. As you complete tasks on your Reminders lists, you can check them off, and keep an archive of completed items so you can track what you've been able to accomplish. What's more, Reminders syncs its data through iCloud, enabling you to stay up to date regardless of whether you're using your Mac or your iOS device.