The first climbing ropes were ordinary manila- heavy, not very strong, easily frayed, and very static. The last one of those characteristics was probably the most dangerous. Even a short fall onto a static, stretch-free rope can be painful or fatal. While we still use static rope (technically it's semi-static) for rappelling, modern dynamic ropes are almost bungee-like in their stretchiness. As long as the anchors hold and there are no ledges or inconvenient trees in the way climbers can safely fall for almost unbelievably long distances these days.
Liberty Mountain Paracord-100 Feet 447388
Sterling Rope 7 mm Accessory Cord (Sold by the Foot) AN700
Sterling Rope 4 Mm Accessory Cord STERLA040AS0100
Sterling Rope 3 Mm Accessory Cord STERLA030AS0100
Equinox Paracord White - 100ft 447501
Liberty Mountain Paracord-100 Feet 447385
Liberty Mountain Paracord-100 Feet 447391
Liberty Mountain Paracord-100 Feet 447380
Liberty Mountain Paracord-100 Feet 447384
Liberty Mountain Paracord-100 Feet 447382
Liberty Mountain Paracord-100 Feet 447401
Liberty Mountain Paracord-100 Feet 447390
Equinox Paracord 100' 447442
Sterling Rope 3/8" HTP Static Rope White / FT P105000183
Rock climbing rope comes in various widths. A wide rope is heavier than a thin one, as you'd expect. The difference is certainly enough to notice at the top of a long pitch or during an extended walk in, but on the other hand, thinner climbing ropes don't last as long as a good quality, durable thick ones. Buying a rope with a dry cover means that it's carefully treated to repel water. Not too important if you'll mostly be climbing indoors but certainly very handy if you're ice or mixed climbing, because if water can't get into a rope it can't freeze, and great for sea cliff situations where the rope might get wet. A good dry cover will also help make your rope last longer, although a rope bag will do more in that area!