if is a record type, where we know exactly all the key names and the value types, we use `{ ... }`, if is an object where we have key - value pairs and where the names of the keys change we use `Object.<string, ...>`, since we actually don't know the names of all the keys or even how many there are. In this case there can be lots of key, value pairs, where the key is always a string that is a language id, and the value the Array, so Object is well used here. Check: http://usejsdoc.org/tags-type.html