A formal or informal methodology for designing, creating, and maintaining software (including code built into hardware).
Source(s):
NIST SP 800-218
under Software Development Life Cycle
The scope of activities associated with a system, encompassing the system’s initiation, development and acquisition, implementation, operation and maintenance, and ultimately its disposal that instigates another system initiation.
Source(s):
NISTIR 7622
under System Development Life Cycle
from
CNSSI 4009, NIST SP 800-34