No, laptop and desktop hard drives are not the same, as they differ in size, power draw, speed, and how they mount inside each system.

No, laptop and desktop RAM share DDR types but differ in size, slots, and voltage, so you cannot swap them directly.

Yes, laptop and desktop RAM differ in size, pins, and slots, so you cannot swap modules directly between these systems.

Most laptop batteries are not universal, since voltage, connectors, shape, and smart electronics must match each specific laptop series.

Laptop CD drives can be swapped in some cases, but connector, size, and mounting parts must match for the new drive to work and fit well.

Most airlines treat a laptop bag as a personal item, separate from your main carry-on, as long as it fits under the seat.

No, laptop and desktop SSD are not always the same, since size, connector type, and power limits can differ even when capacity matches.

A laptop is a portable personal computer, so every laptop is a PC, but many PCs are desk-bound desktop systems.

Yes, laptop bags are allowed on flights as cabin baggage, but airlines treat them differently within your carry-on allowance.

Yes, laptop chargers take AC from the wall and convert it to low-voltage DC for your laptop.