Answer Description
Laptop designs often make it difficult to upgrade or change components like video cards, processors and motherboards. RAM and Hard drives are typically easily accessible and cost effective to upgrade in a laptop.
Wikipedia
Random-access memory (RAM ) is a form of computer memory that can be read and changed in any order, typically used to store working data and machine code A random-access memory device allows data items to be read or written in almost the same amount of time irrespective of the physical location of data inside the memory In contrast, with other direct-access data storage media such as hard disks, CD-RWs, DVD-RWs and the older magnetic tapes and drum memory, the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement
Random-access_memory - Wikipedia, the free encyclopedia