I see what you see... sharing attention and learning about objects

When your baby looks at the same object as you or another person, they will find themselves in something call a ‘shared-attention episode.’ 
 

These moments allow for an exchange of information between them and another person. This helps them to learn about what you're sharing as you look at something together, their thoughts, intentions, the environment in which it occurs and the object. 
 
There is a lot of cognitive processing at play here as your baby processes and responds to both intentional and incidental signalling and gaze between both the initiator of this interaction and the responder. They might be the initiator and you respond, or vice versa.
 
So, just talking about a simple object with your child and looking at it together has many learning opportunities for their cognition, language, and social and emotional development.