Jumping spiders are able to climb glass and other very smooth surfaces because besides having two claws on each foot they also have sticky hairs (called scopulae) that hold onto the surface.
Many tiny ends on each hair are held to the glass by Van der Waals forces, the force that will make two very flat sheets of glass stick tightly together without any glue.

Jumping spiders are able to see very clearly.
Two of their eight eyes are very large and are complicated inside.
The eyes cannot move, so the spider will often move its body to look at what it wants to see.
However, it can also move the retinas of its two main eyes on the inside of the eye, so the center of the eye's picture can be moved.
So the jumping spider has binocular vision.
Jumping spiders are able to climb glass and other very smooth surfaces because besides having two claws on each foot they also have sticky hairs (called scopulae) that hold onto the surface. Many tiny ends on each hair are held to the glass by Van der Waals forces, the force that will make two very flat sheets of glass stick tightly together without any glue.
Jumping spiders are able to see very clearly. Two of their eight eyes are very large and are complicated inside. The eyes cannot move, so the spider will often move its body to look at what it wants to see. However, it can also move the retinas of its two main eyes on the inside of the eye, so the center of the eye's picture can be moved. So the jumping spider has binocular vision.
Jumping spider