What are these red lines on my face? they were on my arms, and have appeared on my neck. they look like scratch marks. they don't itch or anything.

Dermatographism: Dermatographism means the ability to write on the skin. People with this form of chronic urticaria are sensitive to touch and pressure, as well as scratching. The areas of skin that are touched or scratched get a raised red rash. While many people with chronic urticaria have some features of dermatographism, people with true dermatographism have pressure as the only trigger.