Information Technology Reference
In-Depth Information
Chapter 7
Life Cycles
And one man in his time plays many parts,
His acts being seven ages.
—William Shakespeare
The concept of life cycles in the biological sciences defines “life” as an
entity capable of eating, growing, transforming itself, and responding to
external stimuli. The term “life cycle” has been borrowed by other fields
and extended to “nonliving” systems, with the stress being on the cycle
aspect of it rather than the life aspect.
In software, the “input-process-output” paradigm is the seminal life
cycle of all information processing. Benington introduced the first concept
of life cycles in software as early as 1956. The industry accepted the term
after Royce introduced the waterfall life cycle in 1970. Since then, many
categories of life cycles have evolved and are in use today — product
life cycles, product development life cycles, “build” life cycles, software
support life cycles. In fact, we have introduced a new field in “life-cycle
management” — Product Life-cycle Management (PLM), Information Life-
cycle Management (ILM), and the like.
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