Types of software maintenance.
- Corrective: Corrective maintenance of a software product is necessary to rectify the bugs observed while the system is in use.
- Adaptive: A software product might need maintenance when the customers need the product to run on new platforms, on new operating systems, or when they need the product to interface with new hardware or software.
- Perfective: A software product needs maintenance to support the new features that users want it to support, to change different functionalities of the system according to customer demands, or to enhance the performance of the system