The corset is a garment stiffened with rigid materials designed the alter the torso shape of women. They are also used in the 18th century by men.
In the 15th century stiffened front laced bodices existed at the end of that century , but the first corsets appeared in the 16th century and were made from leather or fabric stiffened with wood, horn, whalebone or metal. They were not designed to draw in the waist nor enhance the breasts, rather they were to flatten the chest area and raise the breastline.
By the late 16th century this style had softened somewhat and a smaller waist was desirable but this small waist was not provided by the corset itself, rather this effect was produced by a laced bodice or bandages.
The 17th century saw a variety of corset fashions appear and the French soon saw the corset being used to reduce the waist and a little more room for the bust was introduced. By the end of this century, women had taken up tayloring.
18th century corsets were enhancing more of the female torso losing the straight front. Front laced corsets appear for the less wealthy and rear lacing for those with servants.
The turn of the 19th century saw a bit of a lull for the corset with it falling our of fashion somewhat but it had again become popular by the first quarter of the century. Short corsets to the waist became popular and by the middle of the century, the corset now becomes a support for the breasts. During this century front closures become available, although they are not readily available until the middle of the century.