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]
Binaural beats change the frequency of your brainwaves, giving you control over which category you experience at any given moment. And because you’re in the driver’s seat — and producing specific frequencies to induce a specific state of mind — you can use binaural beats to boost performance, increase focus, get better sleep… the possibilities are endless. “There’s an infinite number of variations on how you could use this kind of technology,” says Bill Harris, Director of Centerpointe Research Institute and creator of auditory brainwave training program Holosync.
Today, EEG machines are used for diagnosing epilepsy and sleep disorders, for determining dosages for anesthesia, and measuring the brain activity of people in comas or suffering from brain trauma. EEG machines also continue to play a role in researching and understanding brainwave entrainment and developing new and better methods for delivering the benefits of this form of brainwave modification. 
Of course, meditation is actually quite a simple procedure, and one that can be practiced anywhere and at any time. There are no special requirements other than the need to have peace and quiet in a distraction-free environment for a few minutes. The trick is being able to switch off from whatever is going on around you and let your meditative state begin.

As a relatively new technology, fMRI has only recently been used to assess brain state changes during meditation. Recent studies have shown heightened activity in the anterior cingulate cortex, frontal cortex, and prefrontal cortex, specifically in the dorsal medial prefrontal area during Vipassana meditation.[7] Similarly, the cingulate cortex and frontal cortex areas were shown to have increased activity during Zen meditation.[8] Both studies comment on the possibility that these findings could indicate some state of heightened voluntary control over attention during mindfulness meditation. Review works by Cahn and Chiesa state that these results indicate consistency in meditation’s effect on these regions of the brain, citing a multitude of other studies spanning other meditative disciplines, but mention the need for further investigation with better controls.[4][6]
I have been using the Equisync CDs at least 24 minutes 5 days a week. It instantly relaxes me, helps get rid of headaches and even hiccups! I have a stressful job and it helps prevent anxiety; I have not had a chance to check my blood pressure but I feel calmer. I have used other products before but I like the Equisync CDs much better; it is deeper and more relaxing.
First of all, thank you for a most remarkable achievement. I have tried products in the past that purported to synchronize meditation-level brain waves — usually overlain by sappy new-age music composed by non-composers — and was invariably disappointed. However, I have been using your Equisync II and Equisync III recordings for a few weeks now and the results are truly astonishing and live up to the claims on your website.

Brainwave Power Music dedicates ourselves to creating original sound therapy music, using unique Musical Compositions, Binaural Beats and Isochronic Tones as our primary sound elements mixed with different instruments and soundscapes to create a relaxed audio environment. We have one main goal: To help others through our music, be it for physical, emotional, mental or spiritual purposes. We constantly upload new music, and continue to work hard to provide new quality music for everyone.
... Several studies have looked at the possible effects of binaural beats within the alpha range on cognitive abilities. A significant improvement in cognitive processing, as measured by the Stroop Effect exercise, was found by a BB stimulation of 10.2 Hz frequency (Cruceanu & Rotarescu, 2013).Carter and Russell (1993)exposed 8 to 12 year old boys with learning disabilities to 8-week long 10 and 18 Hz BB stimulation sessions, and they found an improvement in Raven's progressive matrices and in a subtest of auditory sequential memory (Carter & Russell, 1993).McMurray (2006)assessed the effect of 7 and 11 Hz BB on alpha brainwave activity, working memory, and attention in healthy elderly people, who are known for experiencing gradual decrease in physiological alpha activity. The 2 minutes exposure to BB resulted in an altered electrical activity in the brain. ...
Thanks for your compliment on my article. 🙂 There are some frequency lists which reference and quote some links to metabolism, but I don’t know how effective or reliable that information is. One of the good things but also a drawback of this technology is how accessible it is to use and create tracks. That makes it unattractive for big companies to invest in large-scale research because it’s hard to patent and protect any product they produce based on the research. As soon as they released the frequency data, people like me would produce free videos and cheap MP3s to utilise the research, so they wouldn’t be able to get a good return on their research investment. So to try and gain some insight into what is working for people, at the moment, we are relying upon assessing anecdotal feedback in many areas. Before buying any products/tracks for increasing metabolism, I would look for and try out free videos on YouTube first, to try and gauge how those particular tracks and frequencies work for you.
Some studies have found that binaural beats can affect cognitive function positively or negatively, depending on the specific frequency that’s generated. For example, a study of long-term memory found that beta-frequency binaural beats improved memory, while theta-frequency binaural beats interfered with memory. This is something for scientists to continue to examine closely. For people who use binaural beats, it’s important to understand that different frequencies will produce different effects.

While a practical understanding of brainwaves has been around for as long as people have been singing, chanting, and drumming, a scientific view of the electrical activity inside the human brain was not published until 1924 when German psychiatrist Hans Berger developed a machine for sensing and recording activity in the brain by attaching small electrical sensors to the scalp of his patients and recording the resulting electrical activity. Berger’s inventions and discoveries were built upon the earlier work of Richard Caton who published animal studies on brainwave oscillations in 1875.
Theta waves have another interesting characteristic. The Earth has a measurable resonance of 7.83 hertz known as the Schumann resonance. Because the Schumann resonance is a constant background frequency surrounding all life, it may play a special role in biological activity. The Schumann resonance frequency falls within the range of theta brainwaves and may have something to do with why these brainwave frequencies are so powerful. 

Go behind the scenes of brainwave entrainment technology creation with Joseph Kao, developer of the extraordinary meditation tool Journey to the Center of the Self. Here, in an interview with John Dupuy, CEO of iAwake Technologies, Joe describes the amazing complexity of the brainwave entraining soundscape he created to both accompany his deeply inductive, 30-minute, guided meditation on the first track of Journey, and also stand alone as a music-only track that holds you in a profoundly relaxed, still, yet clear place on the theta/delta border. To find out all that went into the making of the inductive guided meditation on the first track of Journey, see A Guide to Transpersonal Meditation: Journey to the Center of the Self, part I of this interview.
♥ I've suffered from patches of insomnia throughout my life, extending from a few days to dragging on for several weeks, and no amount of the usual proper "bedtime ritual" normally recommended, calms me, as my brain is overactive. Layering combos of the Binaural/Bilateral sounds right before sleep effectively resets me, allowing me to sleep like a normal human. I can't express enough gratitude!
After nearly two years of daily use of this brainwave meditation and brainwave technology, I began to enjoy a quality of life–without medication–that once seemed quite impossible for me. I do not say this lightly. Not only did I enjoy a fulfilling life, I also experienced what seemed like significant development in self-concept, values, interpersonal skills, creativity, accelerated learning, intuition, ability to handle stressful situations, self-esteem, sense of purpose, and social awareness.
While the physiological and psychological processes being uncovered by brain science in the study of brainwaves is sometimes complex and still being investigated, certain basic principles are well-established, easily understood, and helpful for achieving the most effectively use of brainwave entrainment when seeking relaxation, improved sleep, lowering of anxiety, or other goals. This important background information and scientific knowledge presented here includes: 
Newberg found that certain areas of the brain were altered during deep meditation. Predictably, these included areas in the front of the brain that are involved in concentration. But Newberg also found decreased activity in the parietal lobe, one of the parts of the brain that helps orient a person in three-dimensional space. "When people have spiritual experiences they feel they become one with the universe and lose their sense of self," he said. "We think that may be because of what is happening in that area ­ if you block that area you lose that boundary between the self and the rest of the world. In doing so you ultimately wind up in a universal state."

One of the first pieces of research into using binaural beats as a sleeping aid was In a paper called “Tests of the Sleep Induction Technique” published in 1975 by Dr Arthur Hastings. He noted the effects of subjects who listened to a tape containing binaural beats starting from beta slowly descending to delta. Using an EEG machine he was able to monitor the subject’s brainwaves as they listened to the tape, becoming increasingly relaxed before falling asleep. He concluded; “patterns in the various stages suggested that the tape was influencing the subject’s state”.

Study after study has shown that brainwave entrainment technology is an effective way to relieve anxiety[4], and that meditation alters brainwave patterns more effectively than regular relaxation [5]. Dr. Jeffrey D. Thompson refers to the “far-reaching possibilities” to be enjoyed by using “this type of vibrational technology” to encourage healing, emotional release, stress reduction, relaxation and, of course, deeper meditation [6].

I wouldn’t personally recommend listening to delta wave frequencies for depression, so I’m not sure who advised you to do that? People with depression usually have a higher ratio of theta and delta wave activity, so I would normally recommend listening to high alpha wave and low beta wave frequencies, to help balance things. I have some 10Hz alpha tracks for serotonin release, which you can try for free on my YouTube channel here: I also recommend you give these SMR (low beta wave) tracks a try: I hope that helps.
Binaural beats are created when two tones are played simultaneously, one in each ear. As long as the difference between the two frequencies is less than 30 hertz, the brain perceives the difference in the tones as a “beat” which, if listened to with enough focus, the brain will begin to follow (this is known as the “frequency following response”). By changing the difference between the two beats, the brain will change its wavelength and enter into different “states” of being.

What the Neuro Programmer does (as far as I can tell – access to much of the website requires the purchase of product) is present sound and visuals on the computer screen. The user is meant to passively view and listen to this while their brain is effortlessly programmed to solve whatever problem they are having or improve whatever performance they are interested in.
The Alpha state is an intensely pleasurable and relaxed state of consciousness, essential for stress reduction. Alpha is associated with deep physical and mental relaxation, but not quite meditation. Alpha waves instill a sense of mild euphoria, calm your body, reduce Cortisol levels, strengthen your immune system and counteract the negative effects of stress. Alpha waves also increase the production of Melatonin to greatly improve the quality of your sleep.
The only thing I have found lacking in using your product is that there is no place on your website to register my kudos to you for such an excellent product. I am not new to meditation, nor to brain entrainment products, and I found you product to be really outstanding. I’m completely hooked, love listening to the tracks and they are the best way ever to treat monkey mind. Bada boom, bada bing, in just a few minutes any aggravation I’m experiencing in the outside world, melts away and I am one very blissful and happy camper.

♥  I'm an ADHD high school student and I've found that this sound really helps me to get my homework done. Normally, I would be up very late writing essays and studying for tests because I can't sit down and focus on them, but this helps me to focus and also keeps me awake even late at night so I can continue to work. I love this site and I know I'll use it for a long time!