I have several programs that run either on my computer or phone that, when I go to run them, give me a “loading” screen. Back on my Vic-20, this meant that the computer had to load the next game screen or whatever from the cassette drive, but in these machines, the programs are already fully installed. What are they doing? In one case, the delay is almost a full minute, which in computer terms must be forever.
Reading data from the hard drive into RAM. The “loading” phase also includes any initialization that needs to be done - setting up data structures, checking for updates, decompressing files, etc, etc.
…reticulating splines…
phones have really slow bus to the flash memory,
so the load to RAM is a real load.
The software loading stuff .. I believe they may have specified a minimum time to display the message, so even if the actual load time was a minimum instant, the message still shows for the two seconds, for example.
There may be reasons for a load even with modern software,
Games may load textures to RAM (and video card RAM),
Other programs may load , and index, a database in a file , or worse, from many many little files (database in a directory tree type.. thats really slow to load because the disk drive head has to wander all over the drive to get to the files. because the filesystem does try to keep one file non-fragmented, but seperate files can be wildly spread.. )
Some programs ask for a large amount of RAM to be allocated, in order that it can be sure that it has it, this avoids crashes. ("sorry can’t save your work, because I’ve run out of memory and can’t get any more… " .. isn’t nice !)
These answers, while correct, may not be useful to someone who doesn’t know much about how computers work.
A computer has system memory, and storage space. If you think of your computer as a desk, the system memory would be your desktop and the storage space would be the drawers. When you install a program, you’re doing the equivalent of putting file folders in the drawers. To actually work with files, they have to be on the desktop. The drawers can hold more stuff than will fit on the desktop, and when you turn off the computer anything left on top gets swept into the trash.
So basically, when the program is loading, the computer is making copies of the necessary files from the drawers and setting them up on the desktop. When you save your work, the new copies are put in the drawers and the originals are either discarded or moved to an archive. With some programs the system may automatically save the changes as you go.
With your Vic-20 Datasette, the cassettes were the equivalent of the “drawers”, except that it was more like the drawers were across the street and to get the files you had to send your pet snail Gary over to get them a few pages at a time. Computers are much faster now (even the ones in smartphones) so most of your programs load fast enough that it seems instantaneous. The ones that show a “loading” screen are bigger and take a longer time to pull out and set up on your desktop.
No joke. I had to get my spline reticulated the other day. It took forever.