Maintenance is a great application for Mac that lets you complete different maintenance tasks to improve your computer's performance.
Maintenance's features include: repairing permissions, deleting the system cache, fonts and applications; deleting temp files, registers and error logs; rebuilding Launch Services' database, Spotlight's index and mailboxes, etc.
Close all open applications before running Maintenance to facilitate the scanning of the startup disk. Maintenance's help menu is in English and provides detailed information about each of the options included in the program.
