Understanding the nature of information is fundamental to understanding human brain function so let's begin there.

Information refers to the pattern or arrangements of fundamental units that encode knowledge of form or event. The patterns may be temporal (time-varying), such as the patterns of sound that encode speech or music; they may be spatial (two-dimensional), such as the patterns of ink in photographs, drawings, diagrams, maps, and charts; or they may be spatiotemporal, both spatial and temporal, such as the patterns in a motion picture or those that appear on a television set. The pattern units may be analog (continuous) or discrete (digital). For written English the fundamental units are letters and words. The arrangement of letters encodes words and the arrangement of words into sentences, paragraphs, and books encodes meaning. Words are also the fundamental units of spoken language, although some may argue that phonemes or other units of sound smaller than words are fundamental. These differences are unimportant here.

Information is either static (nonvolatile) or dynamic (volatile). Information is stored any time it is represented in a static form. It may also be stored in dynamic form, although the storage would not be permanent. The patterns of ink on a printed page are one example of static information. The groove on a phonograph record is another. The paintings on the wall of a cave or the hieroglyphics in an Egyptian tomb are further examples. The magnetic domains on the recording surface of a disk or the flat surfaces that reflect light in a CD or DVD are all examples of static information. You should easily be able to name dozens if not hundreds of additional examples.

Whenever the stored material remains intact without the need for energy it is static. When stored material needs energy to remain valid it is volatile. When information moves through a transmission medium it is dynamic. The data stored in a computers memory (RAM) is volatile because it requires energy to remain intact. The data stored in a computer's registers is both volatile and dynamic. It is volatile because it requires energy to remain intact and it is dynamic because the registers outputs place signals on the wires that convey data from the registers to the computer's other circuitry. Sound waves of speech are dynamic because they pass through air and light waves are dynamic because they pass through space. Electrical signals in a stereo system or an i-pod are also examples of dynamic information. Dynamic patterns vanish the moment the energy needed for their maintenance or transmission are unavailable. Information must be dynamic to interact with an information processor.