Modern high end digital cameras tend to have a focus button on the back. Grab any DSLR and by default it will focus when you press the shutter button.
Most people do not configure the rear focus button and if they try it out you find that it is difficult to work that way. The people that do use that method swear by it and in fast action shooting being able to focus and shoot independently is a definite advantage.
It took me a while to get used to it, so I forced myself to only shoot that way for over a year, I recommend you give it a try if you shoot action, but it will take a while to get the hang of it.