Rhythm is the arrangement of sounds as they move through time. You can take any of the sounds listed above and arrange them rhythmically to create music. The term rhythm is also used to describe a specific pattern of sounds. In a very simple form, music can be created by clapping your hands to a specific rhythm. There are many aspects of rhythm and several terms related to it that help us to better understand music.

Used to define individual notes by specifying a note value, e.g., whole note (1), half note (2), quarter note (4), etc. and a collection of pitch blocks to define individual tones or chords.
Use to dot any contained notes. A dotted note plays for 150% the length of the original note, e.g., a dotted quarter note is equivalent to a 3/8 note. Double-dotting is not yet supported. (When used with the Tuplet block, the duration of the tuplet is extended by 50%.)
Adjusts the beat of any contained notes by slowing.
Adjusts the beat of any contained notes by speeding up.
Use to repeat any contained notes. Similar to using a Repeat block, but rather than repeating a sequence of notes multiple times, each note is repeated in turn, e.g. duplicate x2 of 4 4 8 would result in 4 4 4 4 8 8, where as repeat x2 of 4 4 8 would result in 4 4 8 4 4 8.
Contains the current beats per minutes, which is by default, 90.
Contains the current beat factor (the default is 1).