
Bondage can be used to restrain a bottom while the top does something else to the bottom or elsewhere. It enhances submission allowing the botton to let go and get into headspace of vulnerability and exposure. It can make the bottom immobile or uncomfortable. Bondage is also used as art to sculpt a bottom in an attractive and erotic manner in order to display and photograph him/her.
Rope is most versatile. It is fluid. Size doesn't matter. It is also most easily obtainable and the cheapest toy. Anyone, once they have learned a few simple knots can be a master. Rope is aesthetically pleasing and provides a challenge to the top to create rather than purchase.
Types of Rope:
Nylon is great general-purpose rope. It is pretty and slick - easy to untie and comfortable but be careful because it is soft and knots can collapse. It's strong, it wears well, but is vulnerable to abrasion, chemicals and sunlight. The ends of cut nylon rope can be prevented from unraveling by heat sealing. Braider rope is easier and smoother; twisted rope kinks up more and tangles more.

Polypropylene is too stiff and hard to work with.
Soft braid cotton is hard to find. Most cotton ropes usually have a core. Cotton holds knots well but it is harder to untie. Wash to make it softer. It gets fuzzy with wear.
Parachute rope is cheap, strong, colorful and good for detail work like CBT.
Traditional hemp rope, manila, sisal, and jute is attractive to some people for its rugged look and its scratchy, uncomfortable feel. It tightens when wet, is more difficult to work because it is harder to untie. It is weaker because it is susceptible to rot. It is sensitive to abrasion, so your bottom might find ways to fray it by rubbing it along a sharp or jagged edge.
Climbing rope is expensive but pretty. It is too too thick for wrists but great for harnesses and excellent for suspension.

For general bondage applications, large diameter rope is preferred because it is less likely to cause circulation problems. Look for softer nylon rope too if you want to avoid chafing . If you use smaller rope, you will need to leave more slack and keep an especially close eye on all extremities. A variety of lengths is useful (upto 50 or 100 ft), and you will certainly need some shorter lengths (6-12 ft).
Taking care of your rope.
Prevent unraveling by dipping, taping, burning or whipping the ends. Washing is good for hygiene, softening and general laundering. Dirt causes inner abrasion and weakens rope. Store rope neatly coiled because kinks and twists can cause undue wear. Keep your rope in a cool, dry place, away from direct sunlight, such as an indoor cupboard or closet. Never store it outside, or even in a garage where fluctuations in temperature and humidity will weaken it and may cause rot. Properly stored rope will last a long time and serve you well. Poor care will cause rope to weaken and eventually to break. This is particularly important to remember if safety could be compromised by rope failure.
Rope stored neatly will also be much more convenient to use during a scene. Don't embarrass yourself by keeping an eager partner waiting while you wrestle with a spaghetti of ropes! Some well-organized bondage enthusiasts find it useful to keep coils of rope sorted or even color-coded by length and type.
General Rope Bondage Safety Issues

1. Make sure you can get your bottom out of bondage fast. Using shorter ropes or quick release knots helps. You should always have safety scissors, too.
2. Risk increases if bottom is left alone or gagged.
3. Be careful not to cause too much strain on joints- wrists, elbows, lower back, knees, hips.
4. Watch out for constriction of nerves and blood vessels. Be alert and communicate. Look for tingling, numbness, abnormal color, coldness in extremeties. Check sides and undersides of wrists, above and below elbows, armpits, tied or arms compressed against body and groin.
5. Use multiple coils to distribute pressure.

6. How tight is too tight? Make sure can fit one finger between bonds and skin. Remember that body parts may swell.
7. Do not tie rope around the neck!
8. Rope Burns can be caused by coarseness of the rope, speed of application (or taking it off) or tightness.
9. If you can only learn one knot the square knot is it. It's easy to remember, easy to tie, and easy to maintain tension while tying. Don't use granny knots! They slip or jam.
Remember that removing rope is just as much fun as putting it on.