Whitepaper

Installing and removing software on the Mac: how it really works

admin · July 24, 2026 · 4 minuten lezen

WhitepaperInstalling and removing software on the Mac: how it really works

Anyone using a Mac for the first time usually misses two things that are second nature on Windows: a setup.exe you double-click, and an “Uninstall a program” panel to get rid of it again. On the Mac it works differently, and that feels unfamiliar at first. This whitepaper explains how installing and removing software on macOS really works.

Three ways to install software

The App Store

The safest and simplest route. App Store apps are reviewed by Apple, install themselves automatically into the Applications folder, and can update automatically afterward.

Downloading from the internet

Software from a developer’s website usually arrives as a dmg file, a disk image, or a pkg file, an installer package. Both end up in the Downloads folder after downloading.

From a disc

Less common these days, but older software may still ship on a CD or DVD. As soon as you insert the disc, it shows up in the Finder as if it were a folder.

Installing a dmg file: the step people often skip

Double-click a downloaded dmg file and a window opens that looks like a separate hard disk. It usually contains the app icon next to a shortcut to the Applications folder. Installing literally means dragging the app icon into that Applications folder. Only at that point is the app actually on your Mac.

After dragging, a temporary disk with the app’s name appears on the left in the Finder. Eject it by clicking the eject icon, then feel free to delete the dmg file from the Downloads folder. That file was only the packaging, not the app itself.

A pkg file works just like on Windows: double-clicking starts an installer with steps you walk through.

Why macOS warns about an “unidentified developer”

Try to open an app that isn’t registered with Apple by a known developer, and macOS shows a warning. This is called Gatekeeper, and it checks whether software comes from a known, verified developer. The safest choice is to look for a version in the App Store, or for an alternative app that is verified. If you are sure the source is trustworthy and want to proceed anyway, it takes a few steps.

Choose the Apple menu, select System Settings, then click Privacy & Security.
Scroll to Security and click Open there.
Click Open Anyway. This button is available for about an hour after you tried to open the app.
Enter your login password and click OK.

The app remembers this exception, and afterward you can just double-click it like any other app.

Removing software: no wizard needed

Most Mac apps are removed without any special program.

Check for an uninstaller first

Some software, especially larger packages, places itself in its own folder that includes a separate uninstaller. If you see something like Uninstall or an App Uninstaller in that folder, use that first.

Drag the app to the Trash

If the app has no separate uninstaller, open the Applications folder through the Finder and drag the app icon to the Trash at the end of the Dock.

Empty the Trash

The app is only really gone once the Trash is emptied. If you are still unsure, you can put the app back until that point via File, Put Back.

Some apps that come with macOS, such as Mail, Calendar, or Notes, cannot be removed. If you get a message that an app is still in use, fully quit the app or restart the Mac before trying again.

What is left behind after removing an app?

Dragging to the Trash removes the app itself, but not always its related settings files. Those are tucked away in the user’s Library folder and usually take up very little space. For most people, it is not a problem to leave them there. If you really want everything gone, dedicated cleanup tools exist that handle this automatically, but that is not a necessity for most home or office users.

Keeping software up to date

App Store apps update themselves automatically, or through the Updates tab in the App Store. Software downloaded from the internet usually checks for updates itself and lets you know through a pop-up inside the app. No manual setup.exe-style action is needed for that.

A step-by-step guide for switchers

Looking for a well-known, widely used app, check the App Store first.
If you land on a developer’s website instead, download the dmg or pkg file and install it following the steps above.
If you get a warning about an unidentified developer, first confirm the source is trustworthy before choosing Open Anyway.
Want to get rid of an app, drag it to the Trash and empty it once you are sure you no longer need it.

A practical scenario for SMBs

An employee who just switched from Windows wants to install a video calling app the company uses. The website has a download button, and after downloading, a dmg window appears with the app icon and an arrow pointing to the Applications folder. After dragging it over and ejecting the temporary disk, the app sits in the Dock, ready to use. A few weeks later an older test version needs to go: a drag to the Trash and an emptied Trash later, the Mac is clean again, without any uninstall wizard ever being involved.