PSP games come on small discs called UMD (Universal Media Disc), the games you will download are images of this discs called ISOs so you will need a Memory  Stick (MS) to store this games. The memory Stick supported by the PSP is the PRO-DUO, but you can also use Micro SD cards with PRO-DUO adaptors. The PSP recognizes up to 32GB of memory. Make sure you get a large stick you can have more games at the same time. Find and remove the lid on the left side of your PSP and insert the MS facing up. Press the PSP "Home" button at the bottom-left of your PSP (it has a the PlayStation logo). Use the cursor buttons to go to "Settings" and then go to the "System Settings" menu. Select the "Format Memory Stick" option. Confirm your action by choosing "Yes" in the menu that appears. Your PSP device will then format the memory stick (it should only take a few seconds). The firmware is the operating system that your PSP uses to store files and execute functions. In order to play downloaded games (ISOs) you will need to "hack" your PSP, this process is explained below but first you need to know which firmware you have:  Click "Home." Browse to and select "Settings." Open the "System Settings" menu. Select the "System Information" option. The firmware version will be displayed on your screen.

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Write a summary of the previous text in Vietnamese:
Mua thẻ nhớ. Định dạng lại thẻ nhớ PSP theo các bước sau. Xác định firmware bạn đã cài đặt.