Both ReRAM (RRAM) and Phase Change Memory (PCM) are non-volatile memories (NVMs) that store data as resistance, but they rely on different physical mechanisms. PCM switches between amorphous and crystalline states using heat generated by electrical current, while ReRAM forms or ruptures a conductive filament within a resistive material. PCM integration typically involves phase-change materials and thermal management considerations, whereas oxide-based ReRAM can be integrated using CMOS-compatible materials in the back end of line (BEOL).