Article: You'll find this in the upper-left corner of the screen. On older Macs, you may need to click Software Updates instead. You'll see this at the bottom of the App Store window. This will install all available updates, including any system updates. Updates for your Mac's video card are included in system updates. You may be prompted to reboot your computer after installation is complete.

What is a summary?
Click the Apple menu. Click the App Store option. Click the Updates tab. Click the Update All button. Wait for the updates to install.