program uninstall

You open up applications folder in Finder and drag the program to the trash bin on your dock. That's how you delete/uninstall. In a nutshell, Mac doesn't work like Windows with complex installs to various locations and uninstall complications.

There is no "format" necessary on Mac. Again, it's not like Windows. The operating system is completely different and doesn't need that kind of attention.

I'm sure people could get into detailed explanations but it just doesn't work like Windows and you don't have to deal with a lot of those Windows issues.

 

The most effective method for complete app removal is manual deletion:

Best way to FULLY DELETE a program​

No. System performance is not affected by what you have stored or installed on your system, unless you're running low on disc space. It's only affected by what you have running.

 

Each program is different. A few come with uninstallers, (most likely in the installer file). Most don't.

However, for the most part. All you need to do is drag the main file from your applications fold to the trash. That's it.

You won't need to reformat due to install/remove. However, you should always pay attention to what you're putting on your system anyway.

That's the short answer.

If you're familiar with the appdata folder on the PC. there is also a /Library/Application Support folder on the mac for each user.

In both cases if you were to uninstall firefox there would still be a mozilla folder left in that directory. To completely remove, you may need to delete data there, etc.. I don't want to make it too complicated, here is a link http://guides.macrumors.com/Uninstalling_Applications_in_Mac_OS_X

There are also uninstallers you can download, but I don't see as needed.

 

Dragging an app to the trash will uninstall the app, but it won't accomplish what the OP asked:

Only the manual method I posted will do that.

 

I whole-heartedly second what this guy said