The bra as we know it was invented in France in 1889. It consisted of two cups with whalebone underwires, all held up by shoulder sashes. Until this time, women were strapped in corsets so tight they would often faint.
Straps can be rigid, semi-stretch or all stretch.
In full-figure styles, straps may be padded for added comfort. Straps do not raise the cups but pull up the back of the bra. If you need to increase uplift, tightening the straps is not the answer. Try a cup style that offers more support. First, they shape and contain the breast.