Area boys (also known as Agberos) are loosely organized gangs of street children and teenagers, composed mostly of males (but with a few females), who roam the streets of Lagos, Nigeria. They extort money from passers-by, sell illegal drugs, act as informal security guards, and perform other "odd jobs" in return for compensation. The groups are based in Lagos Island, a Local Government Area in Lagos and the most urbanised part of Nigeria.

Area boys, who are largely Yoruba, have existed in the city since the early 1980s. However, under various names, types of Area Boys have been traced back to the 1920s. In 2007, the total number of area boys in Lagos was estimated at over 35,000 by a member of the Lagos State Judiciary; as of 1996, the number of them operating on Lagos Island alone was placed around 1,000. A 1996 study of area boys on Lagos Island by Abubakar Momoh showed that only 26.4% of area boys were from Lagos State; Ogun State (22.6%), Kwara State (14.2%), and Oyo State (14.1%) all produced more than 10% of respondents. Most were between twelve and thirty-five years old.

Area is a quantity that expresses the extent of a two-dimensional surface or shape in the plane. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of paint necessary to cover the surface with a single coat. It is the two-dimensional analog of the length of a curve (a one-dimensional concept) or the volume of a solid (a three-dimensional concept).

The area of a shape can be measured by comparing the shape to squares of a fixed size. In the International System of Units (SI), the standard unit of area is the square metre (m²), which is the area of a square whose sides are one metre long. A shape with an area of three square metres would have the same area as three such squares. In mathematics, the unit square is defined to have area one, and the area of any other shape or surface is a dimensionless real number.

There are several well-known formulas for the areas of simple shapes such as triangles, rectangles, and circles. Using these formulas, the area of any polygon can be found by dividing the polygon into triangles. For shapes with curved boundary, calculus is usually required to compute the area. Indeed, the problem of determining the area of plane figures was a major motivation for the historical development of calculus.

A boy is a young male human, usually child or adolescent. When he becomes an adult he's described as a man. The most apparent thing that differentiates a boy from a girl is that a boy typically has a penis while girls do not. However some intersex children with ambiguous genitals, and biologically female transgender children, may also be classified or self-identify as a "boy".

The term "boy" is primarily used to indicate biological sex distinctions, cultural gender role distinctions or both. The latter most commonly applies to adult men, either considered in some way immature or inferior, in a position associated with aspects of boyhood, or even without such boyish connotation as age-indiscriminate synonym. The term can be joined with a variety of other words to form these gender-related labels as compound words.

The word "boy" comes from Middle English boi, boye ("boy, servant"), related to other Germanic words for boy, namely East Frisian boi ("boy, young man") and West Frisian boai ("boy"). Though the exact etymology is obscure, the English and Frisian forms probably derive from an earlier Anglo-Frisian *bō-ja ("little brother"), a diminutive of the Germanic root *bō- ("brother, male relation"), from Proto-Indo-European *bhā-, *bhāt- ("father, brother"). The root is also found in Flemish boe ("brother"), Norwegian dialectal boa ("brother"), and, through a reduplicated variant *bō-bō-, in Old Norse bófi, Dutch boef "(criminal) knave, rogue", German Bube ("knave, rogue, boy"). Furthermore, the word may be related to Bōia, an Anglo-Saxon personal name.