The concept of smart contracts was first conceived by researcher Nick Szabo in the mid 1990s. In his papers, he described smart contracts as a set of promises, specified in digital form, including protocols within which the parties perform these promises. This description can be broken into four pieces:
- A set of promises
- Digital form
- Protocols for communication and performance
- Performance of actions triggered automatically
As you can see, nowhere in this is the blockchain directly specified, as blockchain technology had not yet been invented and would not be invented for another 13 years. However, with the invention of blockchain technology, smart contracts were suddenly much more achievable.
Smart contracts and blockchain technology are independent ideas. A blockchain can exist without smart contracts (Bitcoin, for instance, has no real smart contract ability...