user mode is like what official sony programs use. Kernel mode is the same, but it has more memory and has more access to the psp, making it work better. It does have some compatability issues at times, but if you have a custom firmware, there is no problem.
user mode homebrews go in X:/PSP/GAME3XX/ (The 3XX depends on what custom firmware you are on. if you are on 3.52 m33, it would be GAME352)
kernel mode, or 1.50 homebrews go in X:/PSP/GAME150 (That one is the same on all custom firmwares)
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