Tempo is the speed or pace of the music.
The tempo of the music is usually indicated with an instruction at the start of a piece and often using conventional Italian terms as shown below.
Tempo is usually measured in beats per minute (BPM). A "metronome mark" in beats per minute may supplement or replace a tempo marking.
Common tempi from slowest to fastest:
Dynamics are indicators of the relative intensity or volume of a musical line.
Pianississimo
Extremely soft. Very infrequently does one see softer dynamics than this, which are specified with additional ps.
Pianissimo
Very soft. Usually the softest indication in a piece of music, though softer dynamics are often specified with additional ps.
Piano
Soft; louder than pianissimo.
Mezzo piano
Moderately soft; louder than piano.
Mezzo forte
Moderately loud; softer than forte. If no dynamic appears, mezzo-forte is assumed to be the prevailing dynamic level.
Forte
Loud. Used as often as piano to indicate contrast.
Fortissimo
Very loud. Usually the loudest indication in a piece, though louder dynamics are often specified with additional ‘f’s (such as fortississimo – seen below).
Fortississimo
Extremely loud. Very infrequently does one see louder dynamics than this, which are specified with additional ‘f’s.
Sforzando
Literally "forced", denotes an abrupt, fierce accent on a single sound or chord. When written out in full, it applies to the sequence of sounds or chords under or over which it is placed.
Crescendo
A gradual increase in volume. Can be extended under many notes to indicate that the volume steadily increases during the passage.
Diminuendo
Also decrescendo. A gradual decrease in volume. Can be extended in the same manner as crescendo.
Slurs
A slur is a symbol indicating that the notes it embraces are to be played without separation, i.e. with legato articulation. A slur is denoted with a curved line generally placed over the notes if the stems point downward, and under them if the stems point upwards.
Staccato (Italian for "detached") is a form of musical articulation. In modern notation it signifies a note of shortened duration, separated from the note that may follow by silence.
It is signified with a dot over the top of the note.