A plug-in (small application) used in the Website in the previous problem ceases to work after the move to the new Web server. Steps are taken to find another plug-in and replace the old one. What kind of maintenance is this an example of?

Data from previous problem 

Contrast the following terms:

a. Adaptive maintenance, corrective maintenance, perfective maintenance, preventive maintenance

b. Baseline modules, build routines, system librarian

c. Maintenance, maintainability