What is the difference between RAM and hard disk?

Ram is Random Access Memory which is utilised by your OS to drive any function that the computer initiates, eg. no ram in the computer it wont even start up, or not enough in computer to run something its going to lag due to lack of ram power,
and
Hard Disk or HDD is where information is stored without a HDD an OS cannot exist, sotrage begins with some form of OS then can range from media pictures programs, these internet pages even cache themselves into the hdd at some stage, bost Ram and HDD cant function without each other as they are the main fundamentals that drive a computer in its raw form.
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