The terms Hotrods and
Custom Cars are pretty much interchangeable, but virtually
ANY car can be customized. The term Hotrod assigns a date to the custom
car since Hotrods are older styles of vehicles. What most
people consider to be a Hotrod is
generally a vehicle from the early era of automotive
manufacturing, usually not newer than a 1945 model. Two good examples
of a Hotrod in my opinion are Ford Model-T's, or Model-A's, '32 Fords,
etc, that have been retrofitted with a high performance engine. Other
modifications to these types of vehicles also include the removal of
certain body parts, like the hood, windshield, fenders, or certain trim
which can help to reduce weight. The modification of body parts like
lowering the roof, known as chopping, is also seen on these vehicles.
Vehicles from the 1960's-70's are sometimes called Hotrods too. Calling vehicles from this time frame Hotrods isn't exactly correct. It really just depends on your personal definition of the word. Typically, cars from the 60's and early 70's would/should be called Muscle Cars. These vehicles were produced before catalytic converters were mandatory on production vehicles. Most of the vehicles from this era also featured Giant Engines, like the Chevy 454cid (cubic-inch-displacement) and the Buick 455cid engine. There were many other sizes of engines, but I am familiar with these, and they were both monsters under the hood! These vehicles are frequently customized too! Usually one will see these cars at car shows or local cruise-ins, and they will feature full restorations and some serious customizing! Power windows were unheard of until the early 60's and many car customizers will add this basic feature that we all take for granted in our newer vehicles!
Please take a look at the pictures below (click to enlarge) to see some examples of Hotrods and custom cars!