What is the difference between a Branch and Department?

A branch is a subdivision of a company and is a geographical classification. On the other hand a department  is a classification based on the function, activites or goods. 

A department is a technical area of a office which is under the same premises while the branch is an extension of the office with more or less the same features. 

There is a vast difference between both of them. Both have literally the same meaning,may be you can call any as a "seperate division",but a branch can have a different geographical location but a department always exist within the organization and its location is internal to the organization.

Branches are separated from the main organization. Departments are attached with the main organization under a single roof. Or you can say Branches are of different types like dependent, independent and foreign. There is no such classification in department because all are common under the same roof.