Dermographism is in basic terms...... It is a medical condition that is best described as "skin writing".
Most people have a reaction to their skin being rubbed, often resulting in their skin will turning red. Dermographism is when that red marking also results in a hives type of reaction. The red in combination with the raised hives, make it look like you have been writing on your skin.
The trouble with this condition is that their are many negative social implications. Often people have to watch what they do day by day to avoid situations that result in a dermographism outbreak.
The redness and swelling usually last for at least 15 minutes or more, and are accompanied by a sensation of burning, and or itchiness. These condition related effects often lead to difficulty sleeping, irritability, and general discomfort.