ESP32 is all abuzz. Espressif makes the chips and modules, Ai Thinker uses the chips and makes their own modules. When the ESP32 came out. Ai Thinker started making a module called ESP3212(similar to ESP-12). Espressif also made their modules and calls them ESP-wroom-32. Seeed studio started selling the esp3212 module and later changed the product with updated module called ESP32S essentially killing ESP3212 before it could get in the hands of the masses. Fortunately ESP32S and Wroom have the same footprint and pinout.
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