General mac question

I was just wondering,
On windows after alot of installing and uninstalling, alot of files and folders are left hidden also the registry things are still there and it makes the Pc slower

does this happen with installing and uninstalling software on mac?

No, because the Mac has no registry. Most of any application is in its icon, except for a few text files distributed here and there when the application starts for the first time.

These text files include such things as the app's preferences, or properties — how you set up the app's defaults.

The application icon is a folder full of files, so if you trash the app and empty the trash, 99.9 percent of it is gone.

Some programs can leave a lot of junk as well if they do not have an uninstaller. Temporary files, caches, etc would remain in your ~/Library/Application Support/ folder and perhaps preferences, and other locations as well. Some programs that come to mind are FTP programs, web browsers, anything made by microsoft, etc.

It depends on the program. Some need large libraries and caches. Some leave a tiny harmless preference file.