Can you give an example of a situation where working with legacy or inherited code is required?

Working with legacy or inherited code is often required in the following situations:

• Maintaining and enhancing an existing project that was written a long time ago and uses outdated technologies or approaches.
• Integrating new functionality into a system where some of the code does not meet modern standards.
• Fixing bugs or optimizing performance in old code that cannot be completely rewritten from scratch due to time or resource constraints.

For example, in a PHP project written on an old version of PHP using deprecated functions (such as mysql_* instead of mysqli or PDO), it may be necessary to:

• Update parts of the code for compatibility with the new PHP version.
• Gradually refactor outdated sections to improve security and performance.

This approach allows maintaining the application's operability without risking a complete rewrite of the entire code at once.