What is Smart bridge technology?
Smart bridge technology is the product of Ark project and it should allow to connect and communicate between different blockchains like Etheruem or Bitcoin. Technically it should work, that you will have token Ark, which will have all functions of major altcoins. For example, it should be possible to interact with Ethereum smart contracts.
Basically, the coins were by connected between themselves and Ark will be here only as the intermediary between coins. You look at exact describe of technology on this blog post by Ark team. Also, you can look at Ark whitepaper.