as Apple transitioned from PowerPC to x86 (see MacBook Pro). Note that Core Duo and Core 2 Duo chips are not the same (see Intel Core). The Core Solo CPU was a single-core version of the Core Duo.
Each model includes 2-4 ... an 8-core CPU and an 8-core CPU. The processor integrated memory on board, limiting the device to either 8GB or 16GB of unified memory. The 13-inch M1 MacBook Pro ...