Geographical Structure
As a firm grows it sometimes needs to set up branches in other locations.
A firm may wish to allow these branches to work as autonomous units, that means that they are like little organisations of there own making local decisions but guided by the policy decisions made at the head office.
For example some large 'fast food' chains often work in this way with a head office and suburban branches which are run by a "manager". The head office provides services and support but is not closely involved in the day to day running of the branch. While the branch manager does have scope to make decisions this is limited as compared to a completely separate business.
Functional Structure
In this type of organisational structure the division of work is the most important part. Jobs and activities are grouped together. This is called departmentation. This is a very popular model.
This structure may be varied in a number of ways.
Division by Product or Service.
Here the organisation is divided up according to the product (such as in a supermarket - toiletries, fruit and vegetables, etc.) or the service (such as a local council's sanitation area including waste disposal, recycling, street sweeping and maintenance etc.)
Division by Customer
This could include a sales business which is divided into wholesale and retail sections to cater to the needs of the public and businesses.
Division by process or equipment
A printing firm, for example, may use this sort of division in order to keep all of its printing functions in the one area, for example a screen printing department for T-shirts and a card section for the printing of business cards.
The General structure.
One of the ways in which we can explain the structure of an organisation is through an organisational chart. This charts usually show the title of each managers position and using connecting lines show who is accountable to whom and who has responsibility for which department. It doesn't tell you everything about the organisation such as the communication channels and liaising between departments but it is a useful conceptual tool so that one can think of the organisation as a whole and understand how all its parts fit together.
Towards the top of the structure is usually centred most of the power while as we move down through the structure there is less authority and status.