Multiple pages and Symbols
Your sketches might not be contained to one page and you might even want to share elements between them.
Multiple Pages
All your scriblings can now be in one document, because that's what would make sense; one document and multiple pages. This makes it easy to share with other people as everything is in one place.
Reuse with Symbols
When you're designing a website, you will find you'll want to reuse certain elements a lot; headers, footers and buttons to name a few. Wouldn't it be perfect if there was a single source to edit, and instantly all the others would update? Sketch lets you do this - between multiple pages - with grace and ease.