Stained neurons, courtesy MethoxyRoxy, via Wikipedia
Neurons, or brain cells, are a specialized type of cell which has a central nucleus surrounded by several branches which reach out in all directions. The brain contains several million neurons. It appears the neurons and their interaction are responsible for all brain functions. Neurons do not touch - like nerves, they communicate through the exchange of chemical transmitters, which are released from the end of the neurons.
Most neurons are not active at any given moment. However, as a person tries to perform a task, or focus on a problem, different bunches of neurons start to "fire" or exchange signals. The location of the neurons that fire when a certain task is being performed, such as listening to music, are remarkably similar from person to person.
However, even inactive neurons must be supplied with oxygen and food (generally glucose) on a regular basis. When deprived of oxygen, neurons will die in as little as three minutes. When deprived of food, the brain will lose coordination, resulting in fainting and coma.
There does not appear to be a particular place where memory is stored in neurons. Although it is recognized that memory decreases with the amount of brain damage, there is no location in the brain which, when damaged, will destroy all memory, although it may be impaired.