In the context of traditional software and hardware maintenance, the activities undertaken for the purpose of modifying a system to perform Corrective Maintenance, Preventive Maintenance, Perfective Maintenance, Emergency Maintenance or Adaptive Maintenance. In the context of DevOps, the tools, practices and ideas that support people maintaining a system including version control and configuration management, repeatable build and deployment processes, developer and operation staff collaboration to investigate and solve problems and building and sharing a culture of trust and transparency.