What were the role of Russian guards unit during WW2?

Answer 1

"Guards" is an honorific Stalin allocated to certain uniits that distinguished themselves in combat. Once being awarded that title they received better quality replacements, weapons, uniforms & rations than the run of the mill line outfits. Guards units were all types: infantry, artillery, armor, aviation etc.

Answer 2

"Soviet Guards (Советская Гвардия in Russian, Sovetskaya Gvardiya), units and formations of the Soviet Army, which distinguished themselves in combat during the Great Patriotic War of 1941-1945."

"The title of the Soviet Guards was first introduced on 1941-09-18 in accordance with the decision of the Headquarters of the Supreme Commander-in-Chief (Ставка Верховного Главнокомандующего, or Stavka Verkhovnogo Glavnokomanduyuschego) and by the order №308 of the People's Commissar of Defense for the distinguished services during the Yelnya Offensive. The 100th, 127th, 153rd and 161st Rifle Divisions were renamed into the 1st, 2nd, 3rd and 4th Guards Divisions, respectively. The Soviet 316th Rifle Division was renamed to the 8th Guards Rifle Division on November 18, 1941, following the actions of the panfilovtsy. By 31 December 1941 the 107th, 120th, 64th, 316th, 78th, and 52nd Rifle Divisions had become the 5th through 10th Guards Rifle Divisions. Some twenty Guards Airborne Brigades were converted into 11th-16th Guards Rifle Divisions in December 1943."

"The units and formations nominated for the Soviet Guard title received special Guards banner in accordance with the decision of the Presidium of the Supreme Soviet of the USSR. On 1942-05-21, the Presidium of the Supreme Soviet of the USSR introduced Guards ranks and Guards badges to be worn of the right side of the chest. In June of 1943, they introduced the Guards Red Banners for the land forces and in February of 1944 - for the naval forces."

"After the WWII a number of Guards troops were stationed in Eastern Europe, e.g., in the Group of Soviet Forces in Germany."

"Russian Guards : Soviet Union" : http://en.wikipedia.org/wiki/Russian_Guards#Soviet_Union