Pilates is a mind body practice that was devised by Joseph Pilates in Germany early in the 20th Century. It consists of a series of moves and exercises which are designed to focus the breathe and strengthen the core of the body.
Pilates called his practice controlology and developed the series of moves in an internment camp during World War I. Since then the practice has spread across the developed world and his classes are taught in most first world countries.
Pilates has been shown to help in improving low back pain along with balance and muscle conditioning in otherwise healthy adults. Along with floor and mat exercises Pilates developed a number of pieces of apparatus, including the famous Reformer which is still in use in many Pilates studios today. The Reformer is a sliding bed using spring based resistance which can be adjusted depending on the level of conditioning of the participant.

Much of Pilates work is focused on the breathe and how the core muscles interact with this. It is also based on balance and strength which is where the phrase Contrology was derived from.
While Pilates is quite different from Yoga, it does have some similarities. For example the Yoga poses Navasana and Halasana are almost identical to common Pilates movements.
Today there are instructors, coaches, classes and studios all over the world teaching Pilates original techniques and the popularity of the discipline is only growing.