In the hours after the London bombings of July 7 2005, a website was created for people to air their defiance in the face of the day's terrible tragedy.
It was called: "We're not afraid!" and in a time before hashtags, it was a way for people to express their resolution not to be cowed by terror. Their message was simple: they would not be brought down by the events of that awful day.
When Londoners came together in Trafalgar Square last night to light candles and pay their respects to the four innocent people who lost their lives on Wednesday in the London attacks, their message was just as clear: "We are still not afraid".
After Wednesday's events, there was a determination throughout the city to carry on in the face of it all. The mood at Trafalgar Square was sombre but defiant, as people of all ages and backgrounds stood together, many of them Muslims holding up signs saying: "Love for all, hatred for none".
Among those who came to pay their respects was Jess Okpere, whose teacher Aysha Frade lost her life on Westminster bridge.
Carrying a bunch of daffodils and clearly very emotional, the 18-year-old told the Daily Telegraph: "I cried this morning when I found out. I've had a very long day filled with a lot of tears. I'm here to show that we're not going to let these people win."
Standing on the steps in front of the National Portrait Gallery, faith leaders joined Home Secretary Amber Rudd, Acting Met Commissioner Craig Mackey and Mayor of London Sadiq Khan. Three large candles in glass hurricane lanterns sat before them.
The respectful hush in the square was broken only by applause, as the Home Secretary praised PC Keith Palmer. "He was courageous, he was brave and he was also doing his duty," she said. "It reminded us of how we are all connected."
In an impassioned address, Ms Rudd said: "The terrorists will not defeat us, we will defeat them."
Sadiq Khan spoke of how Londoners had come together in the aftermath of the attack. He said: "London is a great city full of amazing people from all backgrounds, and when Londoners face adversity, we always pull together.
"Our response to this attack on our city, on our way of life, our shared values, shows the world what it means to be a Londoner."
The crowd fell quiet as a minute's silence was observed in honour of the victims. Many bowed their heads, while others clung to each other for comfort. As the silence lifted, people began lighting candles and placing them in boxes filled with sand. Soon, the faces of people all over the square were lit with candlelight.
Amanda Goodhugh, who works at St Thomas's Hospital, where two of the victims were taken on Wednesday, sat on the edge of one of the fountains and cried, her face in her hands.
She told the Telegraph she had been overcome with emotion watching people come together in solidarity. "People's positive response is what is making me so emotional," she said. "That, and the staff at my hospital who ran out into the road yesterday to help. That is what healthcare in this country is all about."