In theory Salsa and Mambo are really the same dance. They are both based on the Clave beat, yet the feel is totally different.
What's the difference step-wise? Primarily, which country's style you are doing. Colombians though Salvadorans dance more side to side like an off time Samba whisk which is because of the Cumbia influence. Cubans and Puerto Ricans dance more forward and back which comes from the Mambo influence. All the young Salsa kids in the clubs are doing more of a nightclub two-step (yes, Buddy Schwimmer's) version than anything else.
Mambo steps are cut it has a quick feet-hold feeling while Salsa has a undulating feeling more like an ocean wave. While Mambo is a stop in the middle dance, many salsa dancers close feet on the end of the pattern (where most mambo dancers would rock fwd or back).
This level should be taken after you have mastered level “1, 2, &3”. In this level you will build on what you have learned in level “1, 2 &3”. In addition, you will learn how to combine your inside and out side turn, and you will be introduce to the in-and-out turn, combining the elements and components of level “1, 2, &3”, and applying timing, leading, and following connection.

