A HEN:Homebrew ENabler (in simple terms, a homebrew loader) with HEN enabled, you can launch homebrew normally like you would on a custom firmware from the game section of the XMB. Once HEN is launched, it remains in memory until the PSP is totally shut off. You must run HEN every time your PSP is turned back on from being completely shut off in order to run homebrew again. This is because all applied patches in memory are lost due to the RAM itself losing powersupply and therefore "forgetting" everything that was once in it.