All phenomena and actions can be expressed as functions. Engineering is really all about satisfying functions. FUNCTIONAL STATEMENT is expressed as (subject) (verb) (object) .
For a given product or process to work, many functions typically are required. A product or process can be described in terms of its parts, and in terms of its functions. The old saying, "Form follows function," means that every form (i.e., every product or process) is a concrete expression of one or more functions.
VALUE = (SUM OF THE BENEFITS ) / (SUM OF THE COSTS). "Benefits" are measured in terms of the functions that a product or process design satisfies. "Cost" includes the raw materials, labor, handling, transportation, processing, and the price of doing business.
The value can be increased by increase of the number and reliability of functions, and by decrease of the cost.
Function-Coast Analysis is presented in the Virtual TRIZ College.