Concepts inImproving computer program readability to aid modification

Readability

Readability is the ease in which text can be read and understood. Various factors to measure readability have been used, such as "speed of perception," "perceptibility at a distance," "perceptibility in peripheral vision," "visibility," "the reflex blink technique," "rate of work" (e.g. , speed of reading), "eye movements," and "fatigue in reading.  more from Wikipedia

Computer program

A computer program (also software, or just a program) is a sequence of instructions written to perform a specified task with a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute the instructions.  more from Wikipedia