A highwayman was a thief and brigand who preyed on travellers. This type of outlaw, usually, travel

Travel

Travel is the movement of people or objects between relatively distant geographical locations. 'Travel' can also include relatively short stays between successive movements.-Etymology:...

led and robbed by horse

Horse

The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

, as compared to a footpad

Footpad

A footpad is an archaic term for a robber or thief specializing in pedestrian victims. The term was used widely from the 16th century until the 19th century, but gradually fell out of common use...

 who traveled and robbed on foot. Mounted robbers were widely considered to be socially superior to footpads. Such robbers operated in Great Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 and Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 from the Elizabethan era

Elizabethan era

The Elizabethan era was the epoch in English history of Queen Elizabeth I's reign . Historians often depict it as the golden age in English history...

 until the early 19th century.

The word highwayman is first known to be used in the year 1617; other euphemism

Euphemism

A euphemism is the substitution of a mild, inoffensive, relatively uncontroversial phrase for another more frank expression that might offend or otherwise suggest something unpleasant to the audience...

s included "knights of the road" and "gentlemen of the road." In the 19th-century American West, highwaymen were known as road agent

Road agent

A road agent can mean:* Another name for highwayman, a criminal engaged in stagecoach robbery in the mid to late 19th century American West. * Road Agent , a professional wrestling liaison between the wrestlers and management...

s.