The SA - Sturm Abteilung- roughly translated as "Storm Battalion" and commonly known as the Storm Troopers division was formed from activists who agressively intimidated opponents to Hitler's Nazi Party, his "National Socialist German Workers' Party." As a para-military wing, it protected campaigning party members during elections and was considered a "support group." It carried out raids and even murdered opposing party candidates.
The SS - Schutzstaffel - made up of SA members,was a protection unit of Hitler's bodyguards, comprised of the most loyal of Hitler's supporters. It was a small, elite force. It expanded rapidly and became the main controller in the elimination of "enemies of the State."
To ensure Hitler's absolute power, the "Blood purge" of 1934 effectively eliminated the SA. It was not disbanded until later but was basically taken over by the SS itself.