• Choose About This Mac from the Apple menu in the corner of your screen. An overview of your Mac should appear, including the model name and serial number.
• Double-click the version number beneath 'OS X' to reveal the serial number if you see a window like this.
• Your Mac model and serial number are also displayed in the System Information app. Select Hardware on the left side of the System Information window after opening the app. On the right, you'll see the model name and serial number
• In the top-left corner of your Mac, click the Apple icon.
• A drop-down menu will appear as a result of this. Select About This Mac from the drop-down menu.
• The information you require, such as processor speed, RAM, and graphics card information, should appear in the resulting window.
• Click the tabs above for further information, such as Storage (to see how much disc space you have remaining) and Memory (to see how much RAM you have and whether you have room to add more).

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