In other words, civil engineering deals with civilization building and maintenance.
They also like to drink beer, crack lewd jokes, and are generally above average in both looks and intelligence thus guaranteeing that they can attract members of the opposite sex and fill the world with more civil engineers.
Civil Engineering defines the branch of engineering which deals with any kind of structure that you don't want to move, (mechanical engineers deal with things that move). The word civil states that this only includes non-military.
A civil engineer can be involved in anything from design to construction, repair or demolition.
Civil engineers either have a degree in civil engineering or are full members (preferably chartered) of an internationally recognised civil engineering institute.
Civil Engineers learn to understand why things do or don't fail (fall down).
If you see something big and man made inclusive of earthworks, buildings, canals, bridges, roads, airports, railways etc etc etc it was most likely built under the control of (and probably designed by) a civil engineer.
engineer 2. yeah, but nevermind it'll do.
engineer 1. you're right let's go for a pint.
engineer 2. good idea, just remember not to drive over this bridge.