When you obtain an
image from a scanner or a camera, it's often too important in size and
weight, so it can be refused by a forum server or by your correspondant.
If you don't want or cannot install a soft on the hard disk, you can easily
reduce ONLINE your picture so it's measurements are 400 pixels and 40
k max., with only 3 clicks. So you can reduce by resizing pictures up
to 8 megabytes.
It's the first step: look for your picture gif,png ou jpeg