no
Back up hard drives are recommended because most hard drives give no symptoms before failing catastrophically. Once they do, it is almost impossible to retrieve data.
No.
The top four brands of 1TB Hard Drives are amongst others Western Digital hard drives, Seagate hard drives, Toshiba hard drives, and Hitachi hard drives.
There are many portable external hard drives which would fit into most standard size pockets.
Cold swapping is the process of replacing a hardware component in a system while it is turned off. This can be done without disrupting the operation of the system but requires it to be powered down. Cold swapping is commonly used for components like hard drives and memory modules in servers and other devices.
Hard disk drives
How are Hard drives indentified and what are their functions
Mac laptops may likely have solid state drives (not hard drives). Those drives are 2.5" form factor and can be replaced by hard drives.
Everything is connected to the motherboard. Everything other than hard drives and disc drives would be directly on the motherboard.
Yes, most hard drives are rewritable. SSD drives can be rewritten to less times than conventional drives, but that is still many times. The OS deletes from hard drives and makes new files all the time. If the hard disk was not reusable, then everyone would be buying them more often, and they would be more easily accessible from the outside of the computer.
Hard drives last for many years
There are tons of kinds of drives. Floppy Disk Drives, CD-ROM drives, PATA Hard drives, zip drives, flash drives, DVD drives, SATA hard drives.... The list could go on and on and on...