Once your application is approved, the next step is publication for opposition.
In the USA, the opposition period is 30 days.
During this time, any third party who does not want your brand registered can come forward and file a Notice of Opposition.
If that happens, your application will have to go through the opposition proceeding, which is like a mini-court case within the USPTO system.
If no third party opposes your mark during the 30-day opposition period, a Notice of Allowance will be issued for your application.