It's the place you go to share your life, but on September 11, it's the place where many shared their memories of one of our nation's worst tragedies.
"I lost my aunt on the second tower," said poster Magdalea Valentin.
"We all held hands and just started praying," said Brenda Slabe.
On September 11, Facebook feeds were dominated by videos memorializing those who died.
"Almost all of us knew someone who was lost that day or someone who had barely escaped," said Brenda Isamoyer.
As one scrolls down the page, dozens of images memorialize our nation's loss.
"God Bless the U.S.," said Steven Ridgeway.
Local residents were also sharing tributes, from the Maltese Crosses in Easton's Centre Square to the Mural at the State Theatre and the larger than life flag at the Mack South fire station in Allentown.
For the most part, the sentiment was clear. Our nation is still dealing with the pain and shock of 9/11, but by posting our feelings on social media, like Facebook, there can be some sense of closure, even though all pledge never to forget.