In JavaScript, generator functions are a special type of function that allows you to use the yield keyword to pause and resume the execution of the function.
The idea is that if a function is called multiple times with the same input, it's more efficient to return the cached result instead of re-computing the result each time.
Data virtualization using Proxies in JavaScript refers to the ability to create virtualized data structures, such as virtualized arrays, that load their data on demand rather than loading all data at once.