Short answers, pulled from the story.
In the early 1980s, the term freestyle described a written rhyme with no specific subject matter that was memorized or pre-composed. Artists like Big Daddy Kane and Myka 9 defined it as bragging about oneself without following a set theme rather than creating lyrics spontaneously.
The meaning of freestyle shifted to refer to improvised lyrics delivered without preparation starting around the early 1990s. Groups such as Freestyle Fellowship helped redefine the concept by treating it like a live jazz solo instead of reciting pre-written verses.
American rapper George Watsky set the world record on the 6th of May 2020 with a duration of 33 hours 33 minutes and 19 seconds. Japanese rapper PONEY broke this title in April 2023 by performing for 48 hours continuously.
Performers often reference places and objects in their immediate setting to demonstrate that a verse is being made up on the spot. They may also take suggestions from the crowd regarding topics to rhyme about during live performances to show spontaneity.
Old school battles required competitors to use only improvised lyrics while modern leagues like King of the Dot incorporate written verses alongside freestyling elements. It remains dishonorable to recite pre-written or memorized raps during traditional freestyle battles because it shows an inability to spit spur-of-the-moment lyrics.