A tenor is a voice type embodied by a male, having one of the highest ranges for that gender. This group has a general set of defining characteristics and is divided further into five specific types identified by characteristics such as timbre, vocal weight, and tessitura, the most comfortable spot for a singer. Sub-types include a leggiero, lyric, and spinto, as well as the dramatic and heldentenor. A sixth type and one usually designated as a separate category altogether, is the typically pre-adolescent countertenor.
Typical range for all tenors stretches from one octave below middle C to a an A4 or high C, depending on the genre. This is a rare voice type, though the bass is the least common. In choral settings, most men are baritones, but sometimes sing the higher part, or it's given to lower altos.
The light-lyric or leggiero Tenor is the male counterpart to a coloratura soprano. This type has great agility and can hit high notes ranging from C3 to D5. As the highest type of tenor, roles are frequently seen in Rossini and Mozart operas, among others. A singer with a warmer quality and brighter timbre than the leggiero is identified as a lyric tenor. This broad category includes many variations in vocal weight, timbre, and tessitura.
Heavier vocal weight and slightly lower range characterize the spinto tenor. The range is typically the same as other tenors, but a spinto may be able to hit several lower notes under one octave below middle C. These roles require a more dramatic quality than leggiero or lyric parts.
A dramatic tenor has the lowest range in this category, being able to reach several notes below C3, and he may have the same tessitura as a baritone. Timbre varies, ranging between darker and weighty to brassy and dramatic. Dramatic tenor roles include the title character in Verdi's Otello and Florestan in Beethoven's Fidelio
The darkest and most dramatic of the tenors is the heldentenor. Range is still high, reaching a high B or C at times, but many are actually transitioned baritones with strong upper registers. This type appears in Wagnerian roles as the protagonist such as Loge in Das Rheingold or Siegfried in the opera of the same title.
Though sometimes classified as its own voice type, the countertenor has the highest range of all male categories. It's typically embodied by pre-adolescent males, and range is comparable to that of a female contralto. Range typically stretches from a G below middle C up to an F one octave above that note.