Skeptics of pornography’s danger will often point out that porn has been around for a long time. After all, cavemen drew sexual images on their stone walls, and the ancient Greeks painted it on their pottery. But comparing ancient paintings on clay vases to today’s endless stream of live action videos depicting every possible sexual act, available 24 hours a day on a device that fits into your pocket isn’t exactly comparing apples to apples.
So what changed? Like most large cultural shifts, nothing happened overnight, but some wheels were already turning back in 1953, the year Hugh Heffner published the first copy of Playboy.
Sex had become a more prominent part of American’s cultural conversation due in part to Dr. Alfred Kinsey, who five years earlier had published a controversial but extremely popular book on sexuality.  He was heralded as one of the first scientists and writers to talk so openly about sexuality.  As a result, his books went flying off the shelves. 
Heffner capitalized on the trend with his magazine. However, to maximize sales, he had to change porn’s image; instead of being thought of as something your friend’s creepy uncle might have, porn needed to look mainstream. To do that, Heffner put pornographic photos next to essays and articles written by respected authors. In Playboy, porn looked like a gentleman’s pursuit.
The next big shift happened in the 1980s, when VCRs made it possible for people to watch movies at home.  For porn users, that meant that instead of having to go to seedy movie theaters on the wrong side of town, all they had to do was go to the back room at their local movie rental place. Sure, they still had to go out to find it, but porn was suddenly a lot more accessible.
And then the Internet changed everything. 
Once porn hit the Web, suddenly there was nothing but a few keystrokes between anyone with an Internet connection and the most graphic material available,  and the online porn industry exploded. Between 1998 and 2007, the number of pornographic websites grew by 1,800%.  According to a 2004 study of Internet traffic in May of that year, porn sites were visited three times more often than Google, Yahoo!, and MSN Search combined. 
And porn hasn’t stayed behind the computer screen. Now that porn is more available, affordable, and anonymous than ever before, more people are becoming addicted  and its influence has soaked into every aspect of our lives.  Popular video games feature full nudity.  Snowboards marketed to teens are plastered with images of porn stars.  Even children’s toys have become more sexualized. 
Television shows and movies have been impacted too as producers and writers have upped the ante with more and more graphic content to keep the attention of audiences accustomed to porn.  Between 1998 and 2005, the number of sex scenes on American TV shows nearly doubled.  And it’s not just happening on adult programs. In a study conducted in 2004 and 2005, 70% of the 20 TV shows most often watched by teens included sexual content and nearly half showed sexual behavior. 
And the more our society becomes sexually saturated, the more porn makers pump out harder and harder material to make sure they stay on the cutting edge. 
“Thirty years ago ‘hardcore’ pornography usually meant the explicit depiction of sexual intercourse,” wrote Dr. Norman Doidge, in his recent book on neuroscience, The Brain That Changes Itself. “Now hardcore has evolved and is increasingly dominated by the sadomasochistic themes … all involving scripts fusing sex with hatred and humiliation. Hardcore pornography now explores the world of perversion, while softcore is now what hardcore was a few decades ago …. The comparatively tame softcore pictures of yesteryear … now show up on mainstream media all day long, in the pornification of everything, including television, rock videos, soap operas, advertisements, and so on.” 
And not only is there more porn to watch, but also there are more ways than ever to watch it.  Today, not only do we have high-speed Internet, we’ve got it on tap for devices we have with us 24 hours a day. Families have gone from having one shared computer to often having multiple personal laptops, smartphones, and tablets. With the launch of Google Glass, it’s now possible to have an Internet-enabled screen in front of our eyes nearly every minute of the day.
As porn’s availability has risen, so have its devastating effects on people (See Porn Is Like a Drug), relationships (See Porn Kills Love), and society (See Porn Leads to Violence & Porn’s Dirty Little Secret) at large.  As therapist John Woods recently wrote, pornography addiction “is no longer just a private problem. It is a public health problem.”