Lindsay Lohan used her time behind bars to brush up on one of her favorite hobbies … writing — and TMZ has learned she plans on turning her work into a profit.

Sources connected to the jailbird tell us Lohan filled up several notebooks during her incarceration … documenting “every single thing about her life” in jail … in the hopes that she can eventually turn the “journal” into a book.

We’re told Lohan wrote about everything from her relationships to her family — and even scribbled about her dreams.


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