Barbed wire
Design: Materials

Zinc-coated steel wire. Galvanized steel wire is the most widely used steel wire during barbed wire production. It has commercial type, Class 1 type and Class 3 type. Or it is also well known as electric galvanized steel wire and hot dipped galvanized steel wire.
Zinc-aluminum alloy coated steel wire. Barbed wire is available with zinc, 5% or 10% aluminum alloy and mischmetal steel wire, which is also known as Galfan wire.
Polymer-coated steel wire. Zinc steel wire or zinc-aluminum steel wire with PVC, PE or other organic polymer coating.
Stainless steel wire. It is available with SAE 304, 316 and other materials.
Strand structure

Single strand. Simple and light duty structure with single line wire (also known as strand wire) and barbs.
Double strand. Conventional structure with double strand wire (line wire) and barbs.
Barb structure

Single barb. Also known as 2-point barbed wire. It uses single barb wire twisted on the line wire (strand wire).
Double barb. Also known as 4-point barbed wire. Two barb wires twisted on the line wire (strand wire).
Twist type

Conventional twist. The strand wire (line wire) are twisted in single direction, which is also known as traditional twist. Besides, the barb wires are twisted between the two strand wire (line wire).
Reverse twist. The strand wire (line wire) are twisted in opposite direction. Besides, the barb wires are twisted outside of the two line wire.

Nominal diameter: 

History: 

Before 1865: Fencing consisting of flat and thin wire was first proposed in France, by Leonce Eugene Grassin-Baledans in 1860. His design consisted of bristling points, creating a fence that was painful to cross. In April 1865 Louis François Janin proposed a double wire with diamond-shaped metal barbs; Francois was granted a patent. Michael Kelly from New York had a similar idea, and proposed that the fencing should be used specifically for deterring animals.
More patents followed, and in 1867 alone there were six patents issued for barbed wire. Only two of them addressed livestock deterrence, one of which was from American Lucien B. Smith of Ohio. Before 1870, westward movement in the United States was largely across the plains with little or no settlement occurring. After the American Civil War the plains were extensively settled, consolidating America's dominance over them.
Ranchers moved out on the plains, and needed to fence their land in against encroaching farmers and other ranchers. The railroads throughout the growing West needed to keep livestock off their tracks, and farmers needed to keep stray cattle from trampling their crops. Traditional fence materials used in the Eastern U.S., like wood and stone, were expensive to use in the large open spaces of the plains, and hedging was not reliable in the rocky, clay-based and rain-starved dusty soils. A cost-effective alternative was needed to make cattle operations profitable.

1873 meeting and initial development: The "Big Four" in barbed wire were Joseph Glidden, Jacob Haish, Charles Francis Washburn, and Isaac L. Ellwood. Glidden, a farmer in 1873 and the first of the "Big Four," is often credited for designing a successful sturdy barbed wire product, but he let others popularize it for him. Glidden's idea came from a display at a fair in DeKalb, Illinois in 1873, by Henry B. Rose. Rose had patented "The Wooden Strip with Metallic Points" in May 1873.
This was simply a wooden block with wire protrusions designed to keep cows from breaching the fence. That day, Glidden was accompanied by two other men, Isaac L. Ellwood, a hardware dealer and Jacob Haish, a lumber merchant. Like Glidden, they both wanted to create a more durable wire fence with fixed barbs. Glidden experimented with a grindstone to twist two wires together to hold the barbs on the wire in place. The barbs were created from experiments with a coffee mill from his home.
Later Glidden was joined by Ellwood who knew his design could not compete with Glidden's for which he applied for a patent in October 1873. Meanwhile, Haish, who had already secured several patents for barbed wire design, applied for a patent on his third type of wire, the S barb, and accused Glidden of interference, deferring Glidden's approval for his patented wire, nicknamed "The Winner," until November 24, 1874.
Barbed wire production greatly increased with Glidden and Ellwood's establishment of the Barb Fence Company in DeKalb following the success of "The Winner". The company's success attracted the attention of Charles Francis Washburn, Vice President of Washburn & Moen Manufacturing Company, an important producer of plain wire in the Eastern U.S. Washburn visited DeKalb and convinced Glidden to sell his stake in the Barb Wire Fence Company, while Ellwood stayed in DeKalb and renamed the company I.L Ellwood & Company of DeKalb.

Promotion and consolidation: In the late 1870s, John Warne Gates of Illinois began to promote barbed wire, now a proven product, in the lucrative markets of Texas. At first, Texans were hesitant, as they feared that cattle might be harmed, or that the North was somehow trying to make profits from the South. There was also conflict between the farmers who wanted fencing and the ranchers who were losing the open range.
Demonstrations by Gates in San Antonio in 1876 showed that the wire could keep cattle contained, and sales then increased dramatically. Gates eventually parted company with Ellwood and became a barbed wire baron in his own right. Throughout the height of barbed wire sales in the late 19th century, Washburn, Ellwood, Gates, and Haish competed with one another. Ellwood and Gates eventually joined forces again to create the American Steel and Wire Company, later acquired by The U.S. Steel Corporation.
Between 1873 and 1899 there were as many as 150 companies manufacturing barbed wire. Investors knew that the business required minimal capital, and almost anyone with determination could profit by manufacturing a new wire design. There was then a sharp decline in the number of manufacturers, and many were consolidated into larger companies, notably the American Steel and Wire Company, formed by the merging of Gates's and Washburn's and Ellwood's industries.
Smaller companies were decimated because of economies of scale and the smaller pool of consumers available to them, compared to the larger corporations. The American Steel and Wire Company established in 1899 employed vertical integration: it controlled all aspects of production, from producing the steel rods to making many different wire and nail products from that steel. It later became part of U.S. Steel, and barbed wire remained a major source of revenue.

In the American West: Barbed wire was important in protecting range rights in the Western U.S. Although some ranchers put notices in newspapers claiming land areas, and joined stockgrowers associations to help enforce their claims, livestock continued to cross range boundaries. Fences of smooth wire did not hold stock well, and hedges were difficult to grow and maintain. Barbed wire's introduction in the West in the 1870s dramatically reduced the cost of enclosing land. 
One fan wrote the inventor Joseph Glidden:

it takes no room, exhausts no soil, shades no vegetation, is proof against high winds, makes no snowdrifts, and is both durable and cheap.
Barbed wire emerged as a major source of conflict with the so-called "Big Die Up" incident in the 1880s. This occurred because of the instinctual migrations of cattle away from the blizzard conditions of the Northern Plains to the warmer and plentiful Southern Plains, but by the early 1880s this area was already divided and claimed by ranchers. The ranchers in place, especially in the Texas Panhandle, knew that their holdings could not support the grazing of additional cattle, so the only alternative was to block the migrations with barb wire fencing.
Many of the herds were decimated in the winter of 1885, with some losing as many as three-quarters of all animals when they could not find a way around the fence. Later other smaller scale cattlemen, especially in central Texas, opposed the closing of the open range, and began cutting fences to allow cattle to pass through to find grazing land. In this transition zone between the agricultural regions to the south and the rangeland to the north, conflict erupted, with vigilantes joining the scene causing chaos and even death. The Fence Cutting Wars ended with the passage of a Texas law in 1884 that made fence cutting a felony. Other states followed, although conflicts occurred through the early years of the 20th century. An 1885 federal law forbade placing such fences across the public domain.
Barbed wire is cited by historians as the invention that tamed the West. Herding large numbers of cattle on open range required significant manpower to catch strays. Barbed wire provided an inexpensive method to control the movement of cattle. By the beginning of the 20th century, large numbers of cowboys were unnecessary.

In the Southwest United States: John Warne Gates demonstrated barbed wire for Washburn and Moen in Military Plaza, San Antonio, Texas in 1876.