The only difference between these two ways of extending types is how they handle conflicts. Interfaces can be merged - types cannot be merged, while interfaces can if you declare them multiple times. The result is pretty much the same as with interfaces, but as long as all fields are different, you can extend types with other types. I'll probably correct them in due time.
Table of contents
1. Interfaces extend syntax is different to types2. Interfaces can be merged - types cannot3. Interfaces cannot extend a primative4. Types can create unions, while interfaces cannot5. Classes can implement interfaces, but not typesConclusionSort: