Every version of Dear John — the books & films, compared across media.
Dear John follows John, a high school dropout who enlists in the Army without direction, and Savannah, the woman he falls for during his leave — until duty and distance test everything they built together. When 9/11 compels John to re-enlist, their relationship survives on letters alone. The same story exists across two media: a novel and its 2010 film adaptation.
Yes. The 2010 film Dear John is an adaptation of the novel Dear John, both following a soldier named John and his long-distance relationship with Savannah.
There are two versions covered here: the original novel Dear John and the 2010 film adaptation, a romance about military service and a love story tested by distance.
The novel Dear John is the source story, tracing John from enlistment through the aftermath of 9/11; the 2010 film Dear John is a good choice if you prefer a visual, romance-focused telling of the same arc.