In music notation, an accent mark indicates a louder dynamic to apply to a single note, or an articulation mark. The most common is the horizontal accent, the fourth symbol in the diagram above; this is the symbol that most musicians mean when they say accent mark. The vertical accent, third in the diagram, may be stronger or weaker than the horizontal accent; composers have never been consistent in using these markings. The vertical accent has many informal names such as a "housetop". In most musical works this type of accent is meant to be played more forcefully and usually shorter.
The remaining marks typically shorten a note. Staccato, the first symbol shown above, indicates that the last part of a note should be silenced to create separation between it and the following note. The duration of a staccato note may be about half as long as the note value would indicate, although the tempo and performers' taste varies this quite a bit. The staccatissimo, shown second, is usually interpreted as shorter than the staccato, but composers up to the time of Mozart used these symbols interchangeably. The tenuto mark, shown fifth above, indicates that a note is to be separated with a little space from surrounding notes. This separation may be enough to emphasize the note, or it may have to be played a little louder, at the discretion of the player. The tenuto mark also indicates that the note should be played for its full value - not cut off earlier. Sometimes these symbols are used in combination.
Even when these symbols are absent, experienced musicians will introduce the appropriate gesture according to the style of the music.