Van der Waals force
In chemistry, the term van der Waals force originally referred to all forms of intermolecular forces; however, in modern usage it tends to refer only to London forces: those forces which arise from induced rather than permanent dipoles. The forces are named after Johannes Diderik van der Waals.
The van der Waals force is the force to which the gecko's unique ability to cling to smooth surfaces is attributed. A gecko can hang on a glass surface using only one toe. In 2003 a kind of synthetic adhesive tape was created using this principle.
all the important stuff's in the other aticles I've linked to.