The collection of eight songs carry no creative titles. Instead, they're simply titled "untitled" with an accompanying date, presumably the date in which the song was recorded. A majority of the songs were recorded in 2014.
Some of the songs have been heard before by Lamar fans as the rapper has performed versions of them during performances on late night shows and during his most recent performance at the Grammy Awards.
The album comes as a surprise as Lamar is still riding high from the success of his sophomore album, "To Pimp a Butterfly," released last year. The album was nominated 11 times and won five Grammy awards.
"Untitled unmastered." appears to be a stripped-down continuation of "To Pimp a Butterfly." In fact, the Compton-bred rapper makes references to songs on the album -- "Mortal Man" and "King Kunta" -- on the new project. It also piggybacks on themes tackled on his sophomore album, such as God, sex and black empowerment. And the album provides more evidence of Lamar's love affair with jazz and live instrumentation.
Still, Lamar made it clear to call this album a "project" and not an album or even a mix-tape. It could be because the rapper plays with cadence throughout and even the songs -- some of which are nearly two minutes long while others are more than eight minutes long -- break the rules of a conventional EP.
Although there's many features on the album, Lamar doesn't credit anyone in typical album fashion. Still, it's pretty clear that label mate Sza is featured on "untitled 4 | 08.14.2014." Also, Cee Lo Green, Thundercat and Anna Wise lend their voices to the project.
Lamar's label head, Anthony Tiffith, the CEO of Top Dawg Entertainment, hinted at a surprise release earlier this week on Instagram. "Ive decided 2 drop a project 1 day this week. I won't say wut day or who. It cud be 2nite So don't ask me jus stay close to the net," he wrote.
No one would've guessed it'd be King Kendrick.