Hope you already read my article series "Collection of Windows Phone 7 (Mango) Tutorials". During the tutorial series, we used the common styles "PhoneTextNormalStyle" and "PhoneTextTitle1Style" in the TextBlocks added to the TitlePanel. So what are those? These are all common styles defined by the style library of WP7 SDK. In this post, we will learn about various font sizes defined in the default style library of Windows Phone 7. So, you don't have to define them again and can reuse those styles which will be standard sizes all over any Phone 7 Applications. Let's discuss them here. Read to know more about it.