(CNN) 2017 was a year when discussions of press freedom and the media's choices reached a new level of intensity.

White House briefings, presidential tweets and rallies critiqued the media.

Journalists pushed back, while engaging in lively debate about the ways they approach their work.

And, perhaps fittingly, the year is about to end with the release of "The Post," a Steven Spielberg film, starring Meryl Streep and Tom Hanks, that retells the story of how an administration tried, and ultimately failed, to stop newspapers from printing a damning government report about the Vietnam War.

Despite the news coverage, the Hollywood treatment and the millions of words of commentary about these issues, just how much do most of us truly understand about why journalists do what they do and why the Constitution affords protection for free expression?