Bitcoin Developer Guide
Can someone who has a better understanding of BTC than me explain something?  How do the escrow-like instruments and other contractual instruments built on top of the block chain work?  How are they better than existing contractual instruments?  How do you guarantee that something that is contractually agreed upon for money (ie: I will transfer you a file, upon me sending the file your funds will be released to me) actually happens?  Or am I fundamentally missing something?Edit: thanks all for replies, learned a lot.