How to set or change Page title of a custom module in magento

If you are making a new Module in magento then you must set your page title. To set Page title in your module write the code below inside your all action of your module Design XML.
You can find your module xml inside
app/design/frontend/default/yourtheme/layout
<reference name="head">
<action method="setTitle"><title> Your Page Title </title></action>
</reference>