Most buildings were built for a particular purpose, which may not always be evident at first glance. The exterior is what we usually see first and it is easy just to concentrate on the façade. This can lead to a rather superficial understanding of buildings, particularly if the focus is on one’s personal reaction to its form and decoration. We build for many reasons: shelter from the weather and protection from noise; security against theft, damage or fire; and privacy. Different activities such as work, recreation, bringing up a family and worship require different kinds of buildings, perhaps in special locations, with varying spaces, environments and forms. The functions of buildings are often complex, and not all are utilitarian, in the sense of serving a practical purpose. Many are designed to express emotions or to symbolise ideas, and this may influence the final form of the building.