# IS Maintenance Practices

System maintenance refers to **making changes or improvements to a system to make it better**. This applies to all types of systems, whether they are developed in-house, purchased as a package, or customized for a specific organization. Maintenance is important because systems are not static and need to be updated or fixed over time.

There are four types of system maintenance practices:

1. **Corrective maintenance**: This involves **finding and fixing problems** or errors in the system.
2. **Adaptive maintenance**: This type of maintenance **adds new features or capabilities** to the system based on user or management requests.
3. **Perfective maintenance**: This focuses on **making the system more efficient** and user-friendly without changing its capabilities.
4. **Preventive maintenance**: This aims to **prevent problems or vulnerabilities** in the system, such as hacking or adding security features.

When users want to request a system maintenance practice, **they usually fill out a form with their name, the date, and the reason for the change**. It's important to also **mention the expected benefits and prioritize the request**. The IT department reviews these requests and decides which ones to prioritize based on their judgment and the information provided.

System maintenance costs can vary over time, **starting high at the beginning, decreasing as problems are fixed, and then increasing again as new features are added**, or the system becomes outdated.