A RAM chip is a small metal device used for temporary storage. More specifically, it is a microchip containing transistors that is soldered onto a circuit board to make a RAM card or module. In mobile devices, RAM (random-access memory) chips are attached directly to the motherboard to save space.
RAM chips come in many varieties, including SRAM (static random-access memory), DRAM (dynamic random-access memory), VRAM (video random-access memory), and others. The picture shows four black RAM chips on a RAM card, which is being inserted into a memory slot.