You can set the page layout for controls two ways in Web forms, using the pageLayout property:
GridLayout— This layout is the kind of layout you see in Windows forms. Using grid layout, you can place your controls where you want them, and they'll appear there in your Web page. You can call this kind of positioning absolute positioning.
FlowLayout— This layout is the standard layout for controls in HTML pages; the browser can move controls as it wants, letting them "flow." Here, controls follow the same layout as words in a page in a word processor—as the page is resized, the words flow to match. You can call this kind of positioning relative positioning.