What do you think objectivity is, and what do you think of it?

Isn't it basically what two people can agree on that is outside themselves? As in, how a thing is observed from a third person perspective? Seems like a necessary component of being able to communicate with one another. I think therefor I am doesn't say anything about how anyone else experiences the world. But we can both perceive a ball fly through the air after either one of us throws it.