Check spelling
You can check spelling automatically, either as you type or at any other time - for example, after you finish creating your slides. When you check spelling automatically, wavy underlines indicate possible spelling errors. If the lines clutter your slide, you can hide them temporarily until you’re ready to correct the errors.
You can also check the spelling of text in different languages. PowerPoint shares dictionaries of other languages and other supplemental dictionaries when installed by other programs in Microsoft Office, such as Word.

¨ Spelling dictionaries
PowerPoint comes with a dictionary of commonly used words that is used when you check the spelling in your presentation. This dictionary is shared with other Microsoft products, such as Word and Microsoft Excel. PowerPoint also shares dictionaries of other languages and other supplemental dictionaries when installed by other programs in Microsoft Office.
When you do a spelling check, you’ll probably see words that aren’t included in the main dictionary. You can add these words to a custom dictionary. Use this dictionary to store uncommon words-such as medical terms or words unique to your work environment.

¨ Auto Spell Check
1. On the Tools menu, click Options, and then click the Spelling and Style tab (Figure 4.5).
2. Select the Check spelling as you type check box. 
As you type, a wavy line appears under each word that is not in the PowerPoint dictionary. 
Tip: To correct the spelling, right-click a wavy line, and then click the option you want on the shortcut menu.

(Figure 2.6)

¨ Temporarily hide the automatic display of spelling errors
1. On the Tools menu, click Options, and then click the Spelling and Style tab.
2. Select the Hide spelling errors in this document check box. 
To display the spelling errors again, clear the Hide spelling errors in this document check box.
¨ Turn off automatic spelling checking
1. On the Tools menu, click Options, and then click the Spelling and Style tab.
2. Clear the Check spelling as you type check box.