In music, tempo is the given speed or pace in a piece of music. The tempo of a piece will typically be written at the start of a piece of music, and in modern music is usually indicated in beats per minute, or BPM. This means that a particular note value, such as a quarter note, is specified as the beat, and the marking indicates that a certain number of these beats must be played per minute.
Some common tempos are: Largo, or suspended; Adagio, or slowly; Andante, or walking, Moderato, or lively; Allegretto, rather lively; and Allegro, cheerful and quickly.
Terms for tempo changes are: Accelerando (accel.), which means to speed up; Ritardando (ritard.), means delaying; Meno Mosso, less movement or slower; Pił Mosso, more movement or faster; Rallentando (rall.), slow down, especially near the end of a section; Ritenuto (riten.), slightly slower, temporarily holding back; Stretto, rushing ahead, temporarily speeding up; and Rubato, free adjustment of temp for expressive purpose.
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Picture of tempo taken by Caitlin