The hashtag, the symbol attached to keywords to tag topics online, on Wednesday celebrates 10 years making social media just a bit more navigable.
The sign has preceded the keywords that mark out all major events around the world since 2007, when it got its first outing on Twitter.
Before long, it had spread to other social media including Facebook[1], Instagram [2]and Tumblr[3].
It was Chris Messina, an American designer and social media expert, who originally proposed using the hash sign (#) - pound sign in American English - to group tweets by subject.
He made the original suggestion in a tweet posted on August 23, 2007 before elaborating in a post online a couple of days later.
He launched the first ever hashtag, #barcamp, to identify a set of conferences focussed around technology and the web that he helped organise.
Messina, who describes himself as an "avid Twitterer", has sent more than 39,500 tweets in 11 years.
Wednesday's birthday celebrations, of course, are trending with #Hashtag10.
#Mobilisation
Today 125 million hashtags are exchanged every day, often serving as a springboard to launch massive online campaigns.
In April 2014 the abduction at Chibok in northeastern Nigeria of 276 schoolgirls by Islamists from Boko Haram led to the posting of the #BringBackOurGirls hashtag.
The then US first lady Michelle Obama was among those who used it to draw attention to the fight against Boko Haram, which at the time seemed to have Nigeria's army on the backfoot.
#BlackLivesMatter was another digital rallying cry, going viral during a wave of protests over the deaths of several black people at the hands of the police in the United States.
Then there...