When feed tracking is enabled for an object, each time one or more tracked fields is updated, a Chatter post is automatically generated.
Two fields on the account have been selected with Chatter feed tracking: Account Name and Account Owner.
Whenever an account owner or name is changed, a Chatter post is generated on the corresponding account record:
Feed tracking is enabled by default for some standard objects. It can be enabled on most standard objects, as well as custom objects.
Configuring Feed Tracking
Navigate to Setup –> Customize –> Chatter –> Feed Tracking. Select object and fields as needed.
Users can view each other’s Chatter feeds and profiles. However, when a user posts to a record, other users must be able to view the record in order to see the post.
I’ve created a new lead, and created a Chatter post on that lead record:
James does not have access to view the lead record I created. When James views my Chatter profile, he will not see posts related to the lead record: