Touch Typing means typing by feeling the touch of your fingers on the keyboard instead of looking for each key as you type.  

Looking for each key as you type is called the "Hunt and Peck" method.   

The hunt and peck method may help with accuracy but it is bad for both posture and speed.

Not many professional typists are hunt and peck typists. 

The hunt and peck method has people leaning over the keyboard putting stress on the neck, shoulders and a few fingers.

A touch typist learns where each key on the keyboard is.  Starting with the Home Keys, they see the keys in their mind without having to look at the keyboard. Once the Home Keys are memorized, every other action flows from there because with every keystroke, the fingers return to the Home Keys helping you to remember where you are on the keyboard.   When you learn where the keys are, you activate muscle memory so that you don't have to think so much as you type.  You will never have to look at the keyboard again.  For example, reaching out to the letter U from the letter J becomes as easy as moving your foot from the accelerator to the brake when driving a car.  You don't need to look at the peddles.   

Because of this and because of better posture touch typistis can type faster and with less chance of repetitive strain injury (RSI).  

Working through will help you to achieve this by words frequently used letter patterns in English (and many other languages).