It affected more young women than any other social group.
News of the blast at Ariana Grande's Manchester concert sent shockwaves online.
Manchester Police tweeted out information while victims let their loved ones know they were okay.
Grande fans took to Twitter with prayers and tears giving the world a glimpse into the horror they had witnessed.
While parents took to the internet to ask if their loved ones were alive, a story has surfaced of a young girl who was missing.
Sixteen-year-old Heather became separated from her friends after the blast.
Twitter user @RileyBlackery instantly took to Twitter asking if anyone had seen her friend.
Thousands of retweets later, a Twitter user by the handle @nathanlamb26 replied with a photo of Heather, assuring her friend she was safe.
Shortly after the incident Grande tweeted about how broken and lost for words she was.
It's believed her World tour has been suspended indefinitely.
The hashtags #PrayForManchester and #RoomForManchester have been trending online.
Local residents have been using the hashtag to offer up support to victims.
People have been offering up their own homes, telling others to donate blood, and taxi drivers free rides to those who need it.
The city's mayor, former Labour MP Andy Burnham, tweeted: "If you are stranded in the area you can... follow #RoomForManchester where hotels and local people of our great city are offering refuge."
A 23-year-old man has now been arrested in relation to the attack.
Social Media Presenter Aziz Al-Sa'afin takes a look at the biggest online trends of the day.
Watch the video for the full interview.
