Embellishing or Nonchord Tones  

What are non-chord tones? Nonchord tones also known as nonharmonic tones are notes that do not belong in a certain chord. In music, they add a little topping or decoration to bring out the music rather than staying dry and boring.

There are several embellishing chord tones that we use in music. 

Passing Tone (PT) - a passing tone is noted that is approached by steps and continues other going up or down in the same direction by step. There is also accented passing tone that occurs on strong beats.

Neighboring Tone (NT) - a neighboring tone has notes that moves using steps. NT can step up or down but must turn to its original note. If a neighboring tone occurs on the second chord it is called accented neighboring tone and is played on weak beats.

Anticipation (ANT.) -  an anticipation note is approached by a step and remains the same note. Anticipation are non accented notes. It is basically a note of the second chord played early. 

Suspension (SUS.) - a suspension note keeps the original note the same and steps downward moving into a next chord. 

In this picture this explains the different types of non chord tones that I mentioned earlier. It shows where each notes goes after being played or after each chord.

Here you can see several more embellishing tones than what I mentioned. In the picture it gives a more dept exploration of how the notes move and which direction they move.

Whiles searching for nonchord tones I came across a video explaining how non chord tones should be certain chord.

Working with chord tones you want to understand the background of what your layering out to have the perfect chord and do not creat any dissonance.