Quantitative electroencephalography (QEEG) is a diagnostic tool that measures electrical activity in different parts of the brain using EEG processing. By using QEEG, it is possible to check the functioning of the brain and determine which areas of the brain have increased or decreased electrical activity, thus revealing the weaknesses and strengths and problems (disorders) of the brain. Disorders such as AD/HD, anxiety, depression, Alzheimer’s, learning disorders, obsessive-compulsive disorder… can be diagnosed using QEEG. To obtain QEEG, first by placing an EEG cap on the head, up to 19 EEG channels or EEG are taken from the person. In the next step, a series of complex mathematical operations (such as Fourier and Violet transforms) are performed on the EEG. The result of these processes becomes a series of images (colored heads) which we call QEEG or brain map. In fact, brain mapping is a method by which we can translate the language of the brain. In the brain map, each colored head corresponds to the activity of a brain wave. The way these waves work together makes us perform properly or improperly. If each of the waves has a proper function, we see the head in green. High activity of brain waves is seen in red and low activity in blue. In other brain imaging methods such as CT, MRI, PET, factors such as cerebral blood flow, metabolism or structural integrity of the brain are measured, while as mentioned, QEEG is a tool that measures the amount of electrical activity of the brain.