Traditional wood rail fence.

Time tested, properly installed and maintained wood plank fencing is superior to most types of fence available. The high cost, however, keeps many horse owners at bay.

You'll see plenty of wood fenced pastures in the communities with big money horses, and for good reason: it is probably the safest fence available.

Strong and highly visible, works in all weather and without electricity.

Small diameter electric twine fence.

This looks like either a very lightweight electric rope fence, or a possibly coated high tensile wire.

Either way, while superior to plain wire, and FAR superior to barbed, the visibility is not as good as properly installed electric tape, thicker braid or other non-electric visual deterrents such as wood or synthetic plank.

Fencing like this should be marked with brightly colored flags every 10-20 feet to increase visibility. Running, bucking horses forget that they "know" where their barriers are.

Electric tape and/or twine fence.

What exactly IS keeping this horse in, anyway?

Even if this is a quality tape fence on the bottom and a good plastic/wire combo thin braid rope fence on top, with electricity, the fence is too low for the horse, inviting a jump if spooked or otherwise motivated. (Perhaps by the green grass on the other side.)

Proper installation is key to making the safer types of fence as safe as possible.

Braided or "rope" fence.

Braided or "rope" fence infused with metal wires and charged with a good electric fencer is far superior to barbed or plain, uncoated wire.

Proper installation is essential; not too much space between posts, tensioners used to keep the fence taut, etc.

Visibility is superior to plain wire, but not as good as wood or synthetic rail.