One of the best proofing tools available in PowerPoint is the spelling check. This is an automated proofing feature which will review the entire presentation for errors. To use this feature, you need to first set the Proofing language from the Language section under the Review ribbon.
In the Language dialog, you can select the language you want to use for your presentation. If you have some content selected, you can click OK and select it for just that section. If you want to use the selected language for the entire presentation you should click default.
Once the proofing language is set you can see it at the bottom of the PowerPoint window. If there are proofing errors in the presentation, you will also see an icon of a book with a red cross on top of it.
You can review the errors in the presentation by clicking on the red cross at the bottom of the window or by clicking on “Spelling” under the Proofing section in the Review ribbon.
From the Spelling dialog, you can take the necessary actions to ignore, correct or edit the errors in the presentation. The table below describes the various options you have in the Spelling dialog.