Since this is a highly specialized and complex science, They cannot offer a complete description here. If you’re interested in doing some research on the internet, use search engines for investigating terms like "backpropagation definition", "backpropagation and biological neural networks", "backpropagation and connectionist systems", etc.
However, it is not necessary for you to fully comprehend the science of back propagation to benefit from the IQ Trainer. You have no need to know anything about this algorithm to benefit from the IQ Trainer. The mechanism to stimulate back propagation and wake up your brain’s neural networks has been built into the software.
All you have to do to increase your IQ up to 40% is to begin training today!