UpdatePanel control is used to perform partial-page update means you can refresh selected parts of the page instead of refreshing the whole page with a postback. In this post, you will get UpdatePanel behavior in different cases without reading more paragraphs or code...:). Let's consider each button will update text of all labels. Now see following diagram, Check sign(✔) indicates the label's modification is displayed and Cross sign(x) indicates no display of changes.

Share your opinion in comment box.