Please tell me
The scientific definition of
(MY NETWORK PLACES)
And I have heard that people are classified according to groups
Like
Star group, baby group
So tell me please this information
Thank you :)

LOL.. There is not 'Scientific' definition for My Network Places. My Network Places is to display all the systems that are connected to the network.

The groups you see is just a classification. So as to let people know who belongs to where. Just like in a company, there would be many departments. So in this case, they classify the users into many different groups (eg, Finance Group, HR Group, etc). In classification, the network administrator can also have a ease of providing access rights to files/folders and equipments. He wouldn't have to select one user at a time to give access but just select the groups instead.