What is your favorite feature of Excel? [poll]

What is your favorite feature of Excel? [poll]:
Its Friday, time for another poll.

This weeks topic is inspired from a discussion Jordan started in our forums (#).

What is your favorite feature of Excel?

I will go first.
My favorite features are,

• Conditional formatting: Quickly highlight something that is not alright (or meets conditions), see trends with data bars or heat maps.
• Pivot tables: Turn data in to understandable information with just a few clicks. When combined with slicers & conditional formats, becomes very powerful.
• Formulas: Ofcourse, with out formulas, Excel would be a glorified notepad!

What about you? What are your favorite features in Excel? Go ahead and tell us by posting a comment.
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