Many people can be confused by these terms. They go to a web site, press a link to start a download, and see a progress bar. A message will tell them that it is finished. But then they wonder why the program isn’t working yet.
Strictly speaking, download means to copy a computer file from a remote computer to the one you are working at. The download ends when the entire file is now on your hard drive somewhere. But the program is not ready to work yet. There is more to be done, especially on windows computers.
Most programs today need to be installed to your computer. Many files are copied to your hard drive, often to several locations. The program will have its own folder, but files are often copied to Windows directories and sometimes to the Documents folder. Then the program will be “registered”. This does not mean at the website of the company that made the program. It means that entries are made for the program in the database called the Windows Registry. Most of the options and settings you choose for Windows and other programs are recorded as entries in the registry.
The file you downloaded in most cases is a program that performs the install, not the actual program itself. It usually has setup or install as part of the file name. A double-click on this file will activate it and start the install process. Often today, this setup program is a small program which goes back to the web and downloads the files for the real install. When this install process is done, your program is ready to use.
While the install is running, be sure to look at the boxes that come up and watch for attempts to load extra programs during the install. I described the hazards of this in the article “Program Installs”.
Now, you could hit the option that says “run” instead of “save” when you are at the site downloading the file. This is a security hazard and should only be done for sites where you have a lot of experience and trust. I never do this because the download process is second-nature to me. I realize that to many this process is not second-nature and perhaps intimidating. However, remember that the crooks and jerks out there are preying on this fear or unfamiliarity. If you are going to be a computer user, it will pay to become familiar with this process.
Finally, I should note that the rise of the app store has changed the scene. Here, you have no option but to install directly from the site. The apps are supposed to be pre-approved, so the safety risk is a lot lower. And the app is ready to use without further action on your part.
Good luck and enjoy your new programs. The web has a lot to offer.