Concentration is basically your mental focus working together with your other senses. The problem however is that there are millions of sensory inputs at any given time. This is much more information than the brain can handle, being able to focus only on any one given input at a time. This means that the brain has to process all of this information and decide on what should be focused on. However this is very difficult since the brain gets easily distracted. This process whereby attention fails and we lose focus is known as inattentional blindness. This means that the information is right there in front of us but we fail to perceive it due to lack of attention. This is the reason why sometimes you might be looking for an object that is right in front of you but fail to see it until someone points it out as being right there. Concentration is pretty hard for most of us, especially in this generation where life is so fast paced and competitive. However as with everything there is a key to mastering the art of focus and therefore concentration. This key lies within repetition and practice. The most effective way of doing this is through methods such as meditation and yoga.