An API is a set of definitions with which software programs communicate. It serves as an interface between different software applications that automatically display the code used to access information and/or functionality without the system having to know how the other program works exactly.
Media Injection connects with social channels (e.g. Facebook) through such an API. The channels decide which features are available for third parties and which are not. This means that we're not always able to implement the same features that are available on the channel itself.
If you're missing any features in MI, just let us know! We can see if the feature is available or not.