Custom firmware (CFW) is a modified version of the original firmware that runs on the PSP. It allows users to install homebrew applications, play backups of games, and access other features that are not available on the official firmware. To check if your PSP has CFW installed, you can follow these steps:
1. Go to the Settings menu on your PSP.2. Select the System Settings option.3. Scroll down to the System Information option and select it.4. The firmware version will be displayed on the screen. If the version number is higher than 6.61, then you have CFW installed.