PHP provides a function to get the width and height of an image. The getimagesize() function will determine the size of image file including flash file(swf).
When users sign up to join your website you may want to verify their email address by sending confirmation link to their email address. You'll learn how to do this in this tutorial.
This HTML text editor brings to the web many of the powerful functionalities of desktop editors like MS Word. It's lightweight and doesn't require any kind of installation on the client computer. Because it is Open Source, you may use it however you want.