Much faster than over the Net. In general, RAM storage disappears when the computer is turned off. If you create a RAM disk, and direct the browser to have its cache there, the whole process speeds up very considerably. There are utilities which take care that RAM disk contents are stored on the harddisk at certain times. Updating the cache Web pages change, being updated with news, and so on.
Some pages change by the minute, others once a month, or never.
There is not much point in storing a page that changes all the time. It would even be wasteful. On the other hand, there is no point in getting a lot of identical copies of a page that never changes. And update the cache. After that use the cache.