The pulse is generated by the sound of a single strike of a drum on a count continuing to be heard on the next count. Salsa's pulse beats occur on the first and third counts and might be provided by the drummer playing the bell of the ride cymbal or be carried in the base line of the music. Accents can occur on the count or anywhere in between. It depends on what type of music is being played and the feel the musicians are after. Thus, for a particular instrument, a bar of music is divided into resonances with accent markers and rests.
Rests describe the duration that an instrument remains silent.
The resonance of a note can start on or before a count and extend beyond it. Accents emphasise a note played by a particular instrument and are used to give feel to the music. As a dancer it is important to pay attention to accentuations in the music, this will allow you to develop dance phrasing. In other words pick moves that visually express the music. Before you started to learn to dance, you instinctively felt the music but once confronted with choreographed moves and steps, many dancers stop listening, and replace the feel with the patterns contrived by their teachers.