The protection of information and information systems from unauthorized access, use, disclosure, disruption, modification, or destruction in order to provide confidentiality, integrity, and availability.
Sources:
NIST SP 1800-10B under Information Security from FIPS 199, 44 U.S.C., Sec. 3542
NIST SP 1800-25B under Information Security from FIPS 199, 44 U.S.C., Sec. 3542
NIST SP 1800-26B under Information Security from FIPS 199, 44 U.S.C., Sec. 3542
NIST SP 1800-27B under Information Security from FIPS 200
NIST SP 1800-27C under Information Security from FIPS 200
NIST SP 800-12 Rev. 1 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-128 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-137 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-18 Rev. 1 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-30 Rev. 1 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-39 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-60 Vol. 1 Rev. 1 under Information Security from 44 U.S.C., Sec. 3542
NIST SP 800-60 Vol. 2 Rev. 1 under Information Security from 44 U.S.C., Sec. 3542
NISTIR 7621 Rev. 1 under Information Security from 44 U.S.C., Sec. 3542
NISTIR 8170 under Information Security from 44 U.S.C., Sec. 3541

  A discrete set of resources organized for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information.
Sources:
NIST SP 800-34 Rev. 1 under Information System from 44 U.S.C., Sec. 3502

  The term 'information system' means a discrete set of information resources organized for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information.
Sources:
NIST SP 800-59 under Information System from 44 U.S.C., Sec. 3502 (8)

  The term 'information security' means protecting information and information systems from unauthorized access, use, disclosure, disruption, modification, or destruction in order to provide integrity, confidentiality, and availability.
Sources:
NIST SP 800-59 under Information Security from 44 U.S.C., Sec. 3542 (b)(1)

  An interconnected set of information resources under the same direct management control that shares common functionality. A system normally includes hardware, software, information, data, applications, communications, and people.
Sources:
NIST SP 800-66 Rev. 1 under Information System from 45 C.F.R., Sec. 164.304

  A computer-based system used by an issuer to perform the functions necessary for PIV Card or Derived PIV Credential issuance as per [FIPS 201-2].
Sources:
NIST SP 800-79-2 under Information System

  A discrete set of information resources organized for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information.
Sources:
NIST SP 1800-10B under Information System from FIPS 200, 44 U.S.C., Sec. 3502
NIST SP 1800-25B under Information System from FIPS 200, 44 U.S.C., Sec. 3502
NIST SP 1800-26B under Information System from FIPS 200, 44 U.S.C., Sec. 3502
NIST SP 800-137 under Information System from 44 U.S.C., Sec. 3502
NIST SP 800-18 Rev. 1 under Information System from 44 U.S.C., Sec. 3502
NIST SP 800-30 Rev. 1 under Information System from 44 U.S.C., Sec. 3502
NIST SP 800-39 under Information System from 44 U.S.C., Sec. 3502
NIST SP 800-60 Vol. 1 Rev. 1 under Information System from 44 U.S.C., Sec. 3502
NIST SP 800-60 Vol. 2 Rev. 1 under Information System from 44 U.S.C., Sec. 3502
NIST SP 800-66 Rev. 1 under Information System from 44 U.S.C., Sec. 3502
NISTIR 7622 under Information System from 44 U.S.C., Sec. 3502
NISTIR 8170 under Information System from 44 U.S.C., Sec. 3502
NISTIR 8286 under Information System from OMB Circular A-130 (2016)

  A discrete set of information resources organized for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information. [Note: Information systems also include specialized systems such as industrial/process controls systems, telephone switching and private branch exchange (PBX) systems, and environmental control systems.]
Sources:
NIST SP 800-128 under Information System from 44 U.S.C., Sec. 3502

  A discrete set of information resources organized for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information. [Note: Information systems also include specialized systems such as industrial/process controls systems, telephone switching and private branch exchange (PBX) systems, and environmental control systems.]
Sources:
NIST SP 800-12 Rev. 1 under Information System from 44 U.S.C., Sec. 3502