Well, the definition is simply "the systematic investigation into and study of materials and sources in order to establish facts and reach new conclusions"

However, I'd like to narrow this to "The systematic investigation into, and manipulation of, a system in order to map variables that can be exploited for material gain"

The reason this is important is because it's important someone can tinker with their website and test out new aesthetics etc.

As for an example of something you'd be hard pressed to get approval for: Body Image & Social Defeat (The Instagram Study). This would be extremely unlikely to pass. Given the research goal would translate to "we wish to see 'how much bullying makes them stay in the cage longer'" then it would be rejected as gratuitous cruelty.