The album's lead single "HiiiPoWeR", was released April 2011. Section.80 sold 5,400 copies in the US solely based upon digital downloads within less than a week, debuting and peaking at number 113 on the US Billboard 200 chart with minimal mainstream media promotion and coverage - however some sources suggest the album entered at number 104. Within a two-week period the album sales had totalled to 9,522. As of October 2012 the album has sold 78,000 copies.
The album is his first studio release, following five mixtapes and an extended-play. Lamar recorded the album at Top Dawg Studios in Carson, California.
The lead single for Section.80 was "HiiiPoWeR", a promotional single produced by Lamar's frequent collaborator J. Cole, of which the concept was to further explain the HiiiPoWeR movement. In the beginning of the music video for "HiiiPoWeR", a quote from Kendrick Lamar reads:
I wrote #Section80 because I was ordered to do so. You'll never understand my life and my world. Have you ever seen a new born baby kill a man? Kendrick Lamar. The very next scene is a visual of me with the eyes of a 6 year old. My mother told me to keep this outtake because it said who I was. An infant looking for answers. Will you forgive me, twice? Probly not. I watch this video and reminisce on that crazy am hour of September 13, 2010. I Got a visit from Tupac Shakur. I remember being asleep. His image said "Don't let me die". I was paranoid. I said "why"? He said "because you the....."
Section.80 is a concept album that revolves around the life of Tammy and Keisha as it explains the personal hardships in their lives. "Tammy's Song (Her Evils)" revolves around two girls cheating on their boyfriends after discovering they were unfaithful, and eventually sleeping with each other because they can't trust men. "Keisha's Song (Her Pain)" is about a prostitute who seeks comfort and control, only to her demise. Lamar explains that Section.80 is for people born in the 1980s until now as he dwells on a variety of subjects, such as referencing Ronald Reagan and discussing how the crack epidemic occurred in the 80s. He explains how this is part of the reason drugs are popular for his Generation (e.g. drug dealing and drug addicts.) "A.D.H.D" addresses the high drug and medication tolerance of people born during the Reagan era. "Kush and Corinthians" notes that justice and morals are rarely cut and dry.
Section.80 was well received by contemporary music critics; it holds a score of 80 out of 100 at Metacritic, indicating "generally favorable reviews". The Smoking Section gave it 4/5 Cigs, declaring "Kendrick absolutely shines...There's no possible way to doubt his conviction."  HipHopDX rated the album 4 out of 5 stars. Pitchfork rated the album 8 out of 10. XXL gave the album a XL/XXL rating. IMF mag gave the album a 9.1/10 rating.Pitchfork Media placed the album at number 45 on its list of the "Top 50 albums of 2011".Complex magazine named the album the seventh best album of 2011.