There are five main categories of brainwave frequencies: Gamma (40Hz+), Beta (13 – 40Hz), Alpha (7 – 13Hz), Theta (4 – 7Hz), and Delta (<4Hz). Each category is associated with a different state of mind; so, for example, when you’re in a peak state of performance, your brain produces Alpha Waves, and when you’re in a deep sleep, your brain produces Delta Waves.
Basically, "two ears." One usage of the word is "binaural recording," which is a form of stereo recording meant to take advantage of the spatial perception of the human ear. Recordings are usually done using a pair of microphones mounted to a dummy head with roughly accurate models of the human outer ear, and the result when played back through headphones is extremely realistic and comparable to surround sound, though following an entirely different recording model. Binaural recordings aren't woo at all, and have nothing to do with binaural beats.[citation needed]
You won’t recall ever being in this state, but it’s an incredibly important brainwave for your health. In this state, you will be deeply asleep, but not actively dreaming. Your body needs this state to heal and regenerate. On a daily basis, you’ll need to achieve this state when you sleep at night to make sure your body can heal itself. When you’re feeling really sick or your body and mind are working hard, you’ll want to stay in this state a little longer.
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For many of us, relaxation means zoning out in front of the TV at the end of a stressful day. But this does little to reduce the damaging effects of stress. To effectively combat stress, we need to activate the body’s natural relaxation response. You can do this by practicing relaxation techniques such as deep breathing, meditation, rhythmic exercise, and yoga. Fitting these activities into your life can help reduce everyday stress, boost your energy and mood, and improve your mental and physical health.
A person might wonder what the problem with looking for validation is; why we shouldn’t seek to compare our experiences with those others have had. Shouldn’t there be some sort of indicators that our practice is producing an effect? There are indicators, but they are not the high profile, odd phenomena most frequently looked for, and they may not become apparent immediately. Some things do take a little time.

Slightly higher-frequency entrainment can lead to hyper suggestive states of consciousness. Still higher-frequency EEG states are associated with alert and focused mental activity needed for the optimal performance of many tasks. Perceived reality changes depending on the state of consciousness of the perceiver (Tart, 1975). Some states of consciousness provide limited views of reality, while others provide an expanded awareness of reality. For the most part, states of consciousness change in response to the ever-changing internal environment and surrounding stimulation. For example, states of consciousness are subject to influences like drugs and circadian and ultradian rhythms (Rossi, 1986; Shannahoff-Khalsa, 1991; Webb & Dube, 1981). Specific states of consciousness can also be learned as adaptive behaviors to demanding circumstances (Green and Green, 1986).  
The mechanism for this is that when your eyes or ears are exposed to a particular frequency of pulses or beats, the thalamus first distributes this information to the entire brain, including the visual and cerebral cortex where neural activity begins to synchronize to the incoming frequency, producing hemispheric synchronization and a balance of brainwave activity across the brain.

When you play a tone with a slightly different frequency into your left and right ear — say, 200 hertz (Hz) in one and 210 Hz in the other — they travel separately to your inferior colliculus, the part of your brain that gathers auditory input. There, the tones “squelch” together into a so-called “beat” at a perceived new frequency. (In this case, it would be 10 Hz.)

Joseph Kao, creator of Profound Releasing, Profound Renewal, and Sound Asleep, is a hypnotherapist and a solution-focused therapist with a private practice in Cambridge, UK. Joe was the co-developer of an acclaimed course on conversational hypnosis, and he regularly teaches hypnotherapy and psychotherapy to other therapists. He has also been the head scriptwriter for over 800 professional hypnotherapy recordings. Joe was drawn to the world of philosophy, meditation, and brainwave entrainment technology from an early age, and he’s had a daily meditation practice since 1998.
If new stressors are challenging your ability to cope or if self-care measures just aren't relieving your stress, you may need to look for reinforcements in the form of therapy or counseling. Therapy also may be a good idea if you feel overwhelmed or trapped, if you worry excessively, or if you have trouble carrying out daily routines or meeting responsibilities at work, home or school.
So using the example track above, the right ear is sent a 20Hz beat, compared to a 10Hz beat in the left ear.  As the right ear receives the higher frequency of beat, this works to increase the speed of the ‘left' brain hemisphere, which can be helpful for people with conditions like ADD, who are often found to have an abundance of slow wave activity in the left brain.

People who handle stress well tend to employ what stress experts call an "optimistic explanatory style." They don't beat themselves up when things don't work out in their favor. So instead of using statements that catastrophize an incident, like "I'm a complete failure," they might say to themselves, "I need to work on my backhand." Or they'll transfer blame to an external source. Rather than saying, "I really blew that presentation," it's, "That was a tough group to engage." Replace the word "expect" with "hope." Expectations can only be used for those things over which you have the greatest personal control. You can expect to quench your thirst with a drink of water. You cannot expect to get the job you just interviewed for. You can hope to get it.

All of this is entirely understandable, even somewhat predictable. Unfortunately, it quickly becomes counter-productive. Such experiences, while having a certain feeling of solidity to them, are largely the product of our desires and expectations. Did your face get flushed? One look in the mirror confirms it did. Was this caused by the entrainment? No, it was not. It was the result of what was sought after and what was expected or even hoped for.

When the track is over you can continue to meditate without the help of the entrainment track.  When you are ready to get up, thank your Higher Self for the experience and remove your blindfold, keeping your eyes closed.  Stay seated with your eyes closed for a few moments, then slowly open them and take a moment to let your eyes adjust to your environment’s light. 
These tones are similar in that they pulse like binaural beats. The difference is that they don’t need to be listened to using headphones as the pulse, or beat, is not generated by two different frequencies. The sound is an on/off pulse. Although you don’t need headphones to seperate the frequencies listened to, they are recommended. I’ve had just as much response to isochronic tones as I’ve had to binaural beats. I’d try both though, especially if you don’t respond to one or the other.
The quickest way to relieve stress is to release endorphins through exercise. An easy way to do this is through shaking and dancing, a form of expressive meditation that loosens your joints as well as clears the mind. It’s one of our favorite techniques to teach in conflict and disaster areas, such as Haiti. Start by standing with your feet shoulder-width apart, knees slightly bent, shoulders relaxed, and shake your whole body for a few minutes (we recommend 7-8 minutes). Then, stop for a minute or two and pay attention to your breathing and physical sensations. Finally, turn on fast music – anything that gets you energized, and allow the music to move you. Don’t feel the need to follow any specific dance moves, just do whatever feels good for you in the moment (it might help to close your eyes). Dance for about 5 minutes, or until you feel satisfied.
Binaural Beats or “binaural tones” are created by playing slightly different frequencies separately into each ear. The difference between the two frequencies stimulates a response in the brain which correlates with this frequency difference. For example, if we present a 100 Hz tone to the left ear and a 105 Hz tone to the right ear, a frequency of 5 Hz is stimulated. This is what is known as the “frequency following response”.
Binaural beats can easily be heard at the low frequencies (< 30 Hz) that are characteristic of the EEG spectrum (Oster, 1973). This perceptual phenomenon of binaural beating and the objective measurement of the frequency-following response (Hink, Kodera, Yamada, Kaga, & Suzuki, 1980) suggest conditions which facilitate entrainment of brain waves and altered states of consciousness. There have been numerous anecdotal reports and a growing number of research efforts reporting changes in consciousness associated with binaural-beats. "The subjective effect of listening to binaural beats may be relaxing or stimulating, depending on the frequency of the binaural-beat stimulation" (Owens & Atwater, 1995). Binaural beats in the delta (1 to 4 Hz) and theta (4 to 8 Hz) ranges have been associated with reports of relaxed, meditative, and creative states (Hiew, 1995), and used as an aid to falling asleep. Binaural beats in the alpha frequencies (8 to 12 Hz) have increased alpha brain waves (Foster, 1990) and binaural beats in the beta frequencies (typically 16 to 24 Hz) have been associated with reports of increased concentration or alertness (Monroe, 1985) and improved memory (Kennerly, 1994).

When you're having a hell of a day—good or bad—checking out for 10-15 minutes is revitalizing. Find a place where you can be alone (and definitely ditch the cell phone)—the attic, the bathroom, a quiet cafe, a big oak tree—and wipe the slate clean for a few minutes. Do whatever it is that relaxes you: Meditate, read a novel, sing or sip tea. It's crucial to take just a few minutes everyday to de-stress. It's not how much time you allot, but being consistent that's important.

The Frequency following response (FFR), also referred to as Frequency Following Potential (FFP), is a specific response to hearing sound and music, by which neural oscillations adjust their frequency to match the rhythm of auditory stimuli. The use of sound with intent to influence cortical brainwave frequency is called auditory driving,[39][40] by which frequency of neural oscillation is 'driven' to entrain with that of the rhythm of a sound source.[41][42]