One of the most vital resources that a computer needs to manage is its memory. All software runs in memory and all data is stored in some form of memory.
The quantity of memory can be vastly different depending on the type of computer.
For example the processing chip embedded in a chip and pin credit card will have a tiny amount of memory to hold its encrypted data
Whilst a super-computer cluster will have petabytes of memory to manage (1 million gigabytes)