used with “or” to say there are two or more possibilities
You can choose to be either white or black when you play chess.
You can choose either the chocolate or vanilla flavor for your ice cream.
The package includes two options, and you can select either the red or the blue variant.
The conference room is available for the meeting either in the morning or the afternoon.
Students can submit their assignments either online through the portal or in person at the professor's office.