In the not very distant past, a periscope was something you would find sticking out of a submarine and snapping wassomething you likely did with your fingers.
But fast forward to 2015 and those same words have come to mean something else in the slippery, fast-moving world of social media.
Periscope is the name of a live video streaming app where you can watch anything from short private videos to full-length fashion shows as they occur in real time.
To "snap" something, in youth lingo, means to post a short video clip of your life on the app Snapchat.
Yup,photos are over. Videos are in.
If you are still posting a picture of your burger to Instagram and giving a Facebook update on its deliciousness, you are not keeping upwith social media trends.
Now, you post a video of you eating it. And then the video disappears in, depending on the app you are using, between 10 seconds and 24 hours.
Periscope and Snapchat are two of the most popular apps in the video revolution overtaking social media. Because smartphones and high-speed Internet are ubiquitous, videos can be produced and watched onthe cheap.
Social media users these days are likely to "snap" multiple times throughout the day, ending up with 15-second videos that provide an off-the-cuff and spontaneous glimpse into their daily lives.
Bystanders are whipping out their cellphones and sharing what they see with Periscope - everything from the contents of their fridge to dramatic events such as the collapse of a building in New York City's East Village, which took place the same day as the launch of the app on March 26.
Most notably, a lot of the content on these apps is ephemeral, meaning you either catch it within 24 hours or it is gone forever.
While Snapchat is still far from as big as traditional social media platform Facebook, which has more than a billion users worldwide, it boasts the fastest growth of all current social media portals - reporting more than 100 million active users posting more than 400 million snaps a day.
As for Periscope, more than 10 million users watch over 40 years of video through the app a day, according to a statement released by the company in August.
But what are the implications now that anyone with a smartphone can be a videographer?
And is giving anyone the access to stream and share video content always for the best?
The mobile video revolution Back in 2013, a little-known app called Snapchat-which allows people to send images and videos that disappear forever moments after viewing - rebuffed Facebook's US$3-billion buyout offer.
Two years later, it seems that Snapchat is having the last laugh. According toTheWall Street Journal, the app is valued at US$16 billion (S$22.5 billion) and has raised more than US$1.2 billion in funding as of last month.
Its financials make it the fifth highest-valued private venturebacked company in the world, putting it in the same company as start-up successes such as Uber and Airbnb.
And even though it remains without a definitive revenue stream, it has the fastest-growing user base of any social media site, a majority of whom are in the 14 to 25 age group that is coveted by advertisers. In contrast, Facebook's user base averages around 40 years old.
Snapchat's newest feature, called Discover, has seen it partner notable publishers, including CNN, Yahoo, Vice and National Geographic.
Through these content channels, publishers can post news stories daily and users can get news without leaving the app.
Periscope, which was acquired by Twitter in January for an undisclosed sum, has become a video extension of tweeting.
The app allows people to capture or watch live video broadcasts ontheir smartphones. Unlike the passivity of watching television or videos on YouTube, Periscope is active.
While watching a live stream through the app, viewers are able to comment, ask questions and "heart" broadcasts in real time, letting the person behind the recording know the immediate audience reaction.
Thanks to Periscope's access to Twitter's population, users can also send a push notification to their Twitter followers when they begin to live stream, enticing followers to either tune in or miss out.
Unless saved, streams appear on the app for 24 hours before they disappear. Snapchat and Periscope are not the only ones on the mobile live video streaming market.
Periscope's biggest rival, Meerkat - which was released a week earlier but had many of its functions blocked on Twitter after the launch of Periscope - also offers live stream functions, just without the option to save videos for later.
And coming out of South Korea, an app known simply as V broadcasts daily videos featuring top K-pop talent such as boyband Big Bang.
Though users cannot post their own content through the app like they can on Periscope and Snapchat, they can still comment on and "heart" the broadcasts while they watch them, giving fans a chance to interact with their favourite stars in a whole new way.
Now you see it, now you don't The element of getting news in real time is the apps' biggest draw. Mr Simon Kemp, 37, regional managing partner at social media consultancy, We Are Social, says that when it comes to mobile live streaming, the appeal is in the immediacy of the content.
"The spontaneity that video offers gives celebrities, brands and even the average Joe a chance to get immediate feedback about the content they're putting out there," he says.
"It keeps users tied to the app and incentivises checking in in a different way from traditional platforms of social media such as Facebook or Instagram."
It is a very attractive feature to young users.
Polytechnic student Monica Heng, 20, started using Periscope in June to watch fashion shows streamed live.
She says: "Lots of these live streams are not saved and can't be replayed, so they entice me to check what is available every day."
Public relations executive Hazwan Norly, 24, likes how Snapchat's content is ephemeral, which allows him to be "more randomand in the moment". He has a group of about 20 close friends on Snapchat.
He says: "It's a fun way to document my day and see what other people are up to, while feeling safe in the knowledge that everything I upload will be deleted in 24 hours."
So what is Kylie Jenner up to today?
Celebrities love Snapchat and Periscope.
Famous early adopters turned evangelists are reality star Kylie Jenner, singer Ariana Grande and actor Jared Leto.
For store manager Farah Noh, 30, Snapchat allows her to peep into the lives of celebrities such as singer Rihanna, "who are a lot more relaxed in their snaps compared to their Instagram posts", she says.
National serviceman Richmond Goh, 19, agrees, saying he has been using V and Snapchat for the past year to follow news of his favourite K-pop stars, DJs such as Martin Garrix and Avicii, and MediaCorp actresses Zoe Tay and Fann Wong.
"It's so much more personal than just pictures or status updates - plus I like being immediately privy to insider information such as new song releases," he says.
Loyal Snapchat and Periscope users are definitely seeing the benefits.
In February, Madonna premiered her first music video from her new album on Snapchat.
Guardians Of The Galaxy (2014) director James Gunn used Periscope to answer fan questions in April and gave exclusive details about the upcoming sequel to the Marvel blockbuster.
Brands are jumping on the bandwagon too. Some use Snapchat and Periscope to debut new products and events to the apps' young millennial users.
Luxury British fashion house, Burberry, for example, showcased its spring/summer 2016 collection on Snapchat in September - ahead of its show at the 2015 London Fashion Week.
In the United States, brands such as music streaming service Spotify and soft-drink Mountain Dew have used Periscope to engage with their followers.
In Singapore, brands are still cautious about using these apps to market their products.
However, Mr Steve Kalifowitz, brand strategy and advocacy lead at Twitter Singapore, is optimistic, saying he is seeing interest from industries such as telecommunications and finance as well as consumer brands.
"Four in 10 users of Twitter in Singapore are using video inside the app, so the movement to Periscope is very natural.
We're hoping to see the first few brands experiment with using the app in South-east Asia within the next twomonths."
Blurred lines Video streaming raises legal issues when users stream copyrighted or licensed content without receiving permission.
Take, for instance, the celebrated match between boxing legends Floyd Mayweather Jr and Manny Pacquiao in May, when numerous Periscope users live streamed the game (which was broadcast under pay-per-view agreements) for free on Twitter.
Mr Jonathan Kok, 52, partner in the Intellectual Property and Technology Practice at RHTLaw Taylor Wessing LLP, says that "if individuals stream or distribute content on Periscope or Snapchat with copyrighted material - during a concert or sporting event, for example - the organisers of the event who own the broadcast rights have the right to go after themfor copyright infringements."
But for now, it seems that the benefits of live streaming greatly outweigh the cons.
Case in point? In April, 40 million people from around the world tuned in to Snapchat to watch a live stream of the annual Californian music festival Coachella.
This is nearly double the 24.8 million television views drawn by the Grammy Awards ceremony in January.
Such solid numbers suggest that the tide is slowly turning towards the digital sphere, with video live streaming leading the charge.
If Facebook, Twitter and Instagram are about putting your most-filtered and carefully curated face forward, then the ephemeral nature of this next generation of social networking promises to do the exact opposite: Allow users to see, hear and comment on life - as it unfolds in real time.
This article was first published on November 8, 2015.
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