Why any html button cause postback in aspx page?

Question

I have created .aspx page on my SharePoint site and inserted within the page HTML button.

Example

    <PublishingWebControls:editmodepanel PageDisplayMode="Display" runat="server" SuppressTag="True">
...
<button>Click Me!</button>
...
</PublishingWebControls:editmodepanel>

Every time I hit 'Click Me!' the post back occurs. This is not my desired behavior, but I have found a way how to not cause post backs. I added javascript code to onclick property <button onclick='return false;'>Click Me!</button>

My question is, why the post back occurs, even if the button does not contain type="submit" property?

I checked also master page, which contains <form runat="server"> and wraps all the content and there is also no action="page.aspx" property.

Answer 1

Check this link, http://www.w3schools.com/tags/tag_button.asp There is a note on page, which says, that different browsers can use different default type for button, if you don't specify it by yourself. Seems like your browser uses "submit".