Electricians and electrical contractors are closely related and work closely together but are often confused.  Electrical contractors employ the electricians and are in charge of designing and implementing the plans for an electrical system.  For example, electrical contractors will design the electrical system for a house and hire electricians to put it in the house.  An interesting side note is that, in many locations, an electrician cannot work unless under the supervision of an electrical contractor.  This is for safety reasons; electricity is dangerous and only accredited system designers should be allowed to design the circuitry for a house.

Electricians are the individuals who actually implement the systems being installed or repair the systems that have broken.  They have their own accreditation process and training protocol but it is much different than the electrical contractors.  The contractors must be certified in designing safe circuits where the electricians but be certified in working hands-on with the systems.

There are two major functions that residential electrical contractors perform.  Creating and implementing electrical systems for new homes or repairing electrical systems that broke. 

Implementing these systems in new homes is somewhat clear-cut.  Most companies have one or a few different options that they can choose based on how appropriate they are to the home being considered.  Of course they are always developing new ones but the electricians become very skilled at installing these systems since it is the same or very similar every time.  This is especially true in developments that use the same blueprints for every house.  They go in, install the system, and get out very quickly since there is a step-by-step process given to them.

Where it gets more complicated is for electrical home repairs.  Though many systems have self-diagnosis systems, many do not and this can complicate things.  For something extremely complicated it is almost always easier to install a new system than to diagnose a serious problem with it.  This is certainly the case in circuitry because of the sheer number of parts that could have defected.  There are definitely ways to diagnose the problems but it is still a tricky process.

The electrical contractors are responsible for the electricians they employ.  They must not only be the brains behind the operation but also make sure that all of the systems they design conform to safety standards and work correctly.  Electricians work for electrical contractors; they implement their designs and repair faulty ones.  A brand new system definitely requires the services of an electrical contracting firm but an electrician can often do repairs if the damage is not too bad.