Is DDR4 RAM compatible in a DDR3 RAM slot?

Slots for DDR4 memory in motherboard, isolated on white — Photo ddr4 slot Buy Original DDR4 Slot NEW For Laptop Lenovo Thinkpad DELL HP ACER ASUS Motherboard Memory DIMM RAM Jack Socket Connector at Aliexpress for ddr4 slot Up to DDR4 3200 MTs; Max # of Memory Channels 2; Max Memory Bandwidth GB The socket is the component that provides the mechanical and

ddr4 slot vs ddr5 DDR4 DIMM Memory Slot part of motherboard, mainboard, system board, main circuit board, or baseboard main printed circuit of computer DDR