There is never a moment at which you could do everything you’ve decided to to, simply because most of those actions require a specific tool or location. Context is also the first criterion that limits your options and keeps you from being reminded of things you simply can’t do.
If you’re like me, and find it useful to track of all things to talk to your spouse about, stuff to pick up at the store, and emails you need to compose. It’s a lot easier to simply turn to a list that already has things to do sorted by their context, where you can see your eight calls in one click glance.- David Allen
Some suggested contexts to get started (p.144 of Getting Things Done):
- Waiting For
- and lists for Projects and Someday Maybe
For more detail on setting up contexts, check out the GTD Setup Guides.