The neighborhood where the film takes place is the same street where the film's director, F. Gary Gray, grew up in South Central, Los Angeles. Principal houses that were used for filming were houses of old friends of the director. The scene where Deebo punches Red into the air is the house that Gray grew up in.
The cast and crew were warned well ahead of time not to wear anything red during filming. 126th Street where the film was shot was well inside the territory of the Crips street gang, known for wearing distinctive blue bandannas, whereas their bitter rivals, the Bloods, wear equally distinctive red bandannas. So for their own safety, red clothing was banned from the set, because anyone wearing red clothing of any kind, bandanna or otherwise, would be assumed to be sympathetic to the Bloods, and potentially be attacked on sight by the Crips.
In the flashback scene where Smokey is in the car with Hector and his friend, two men can be seen sitting on a block wall in the background. The men were residents of the neighborhood who wanted to be difficult towards the production staff, knowing they couldn't tell them what to do on their property. They remained in the shot despite offers from the staff which included compensation or a walk-on role in the film.
In the theatrical version, we are immediately introduced to the Jones family. The extended version of the film introduces viewers to several supporting characters (Deebo, Ezal, Stanley, etc.) before the Jones Family.
The song being played on Smokey's car while Smokey and Craig were about to go to a store was performed by Dr. Dre, a former member of N.W.A. just like Ice Cube (Craig). It is also remembered that Dr. Dre along with other N.W.A. member were once dissed by Ice Cube through his rap "No Vaseline" though during the making of this film they've already settled down their differences.
In the telephone scene where Craig's girlfriend Joi (Paula Kai Parker) accuses Craig of cheating on her, if you look closely directly behind Joi, you can see another man laying in her with his back to the camera
The trivia items below may give away important plot points.
The outfit that Ice Cube wears throughout the movie is also the same outfit worn by Ice Cube's son in the movie Straight Outta Compton. it's in the scene when the news reports Eazy-E having aids. O'shea Jackson Jr. plays as his father in the movie. The movie also shows O'shea Jackson Jr. (as Ice Cube) writing the script to Friday.
Ice Cube (Craig) Bernie Mac (The Reverend), AJ Johnson (Ezel) ,Tiny Lister (Deebo) , Faizon Love (Big Worm) and Ronn Riser (Stanley) all appear together 3 years later on Players Club which was also written and directed by Ice Cube.