OK - another slant -
TIMING
timing of movement may or may not be music.
obvious, really!
however, for ballet, mostly it WILL be music, so i'll just talk about music, but the same principles apply to whatever else might be providing the timing.
a single beat is referred to as a "pulse beat". this beat is a crotchet value, unless otherwise stated.
a 4/4 will have 4 pulse beats, or 4 crotchet values per bar. a 2/4 will have 2. a 3/4 will have 3, and so on.
within that structure, further divisions are indicated by sub-beats (which i won't go into, any further, right now).
the basic rule is, that if there are equal numbers of notated positions in a bar, and crotchet values in that bar, then it will be one position per note (value), unless further information is provided to contradict that.
here is an example where 'further information' WOULD be necessary:
1 tendu devant, (count 1)
close 5th, (count 2)
1 quick tendu devant to 5th, (and 3)
hold in 5th (count 4)...
there will be 4 notated positions in that bar of 4/4:
the tendu, the 5th, the tendu, the 5th.
- but one position is on a sub-beat ("and') and another beat has NO movement on it.
there are benesh symbols, to write above the stave, for the sub-beats, if and when you need to use them.
and for the 1-count 'hold', you write the pulse beat symbol (a circle with a vertical line straight through it) above the relevant empty stave-space, to indicate that the beat occurs there - but movement doesn't.
below, i will see if i can find you an example of the use of such symbols...