1. TikTok is an app for making and sharing short videos.

2. The videos are tall and long, not square-shaped like on Snapchat or Instagram stories.

3. You navigate through videos by scrolling up and down, like a feed, not by tapping or swiping side to side.

4. Video creators have all sorts of tools: filters like Snapchat and IG, and endless sounds to score your video.

5. Users are encouraged to engage with other users, through video responses or via “duets”—users can duplicate videos and add themselves alongside.

6. Like with Twitter, hashtags are important on the platform, allowing users to connect to blobs of activity around dance challenges, song snippets, or jokes.

7. You can select from an enormous range of sounds, from popular song clips to short moments from TV shows, YouTube videos or other Tik Toks.

8. This particular functionality is what has led to TikTok’s powerful influence over viral music; most recently demonstrated in the rise of Lil Nas X and Joji.

9. Twitter and Instagram—where you follow people and are followed in return—evolved their social-media experience from hashtags and retweets/reposts to more algorithmic recommendations on user feeds, based on both expansion and discovery but rooted in their core structure: Facebook News Feed, Instagram feed, Twitter scroll and their strict user relationships. Even Vine had the old social-media dynamic of “following” for content.

10. Tiktok is different; it provides a main page called “For You,” which is an algorithmic feed based on videos you’ve interacted with or just watched. It never runs out of material and is distinctly NOT full of people you know or things you said you wanted to see. It makes assumptions based on past history and what it learns as you interact with the app.

11. “Imagine a version of Facebook that was able to fill your feed before you’d friended a single person. That’s TikTok.”

12. All social networks require you to provide the content and grind to build your audience. TikTok puts you in different friend groups, exposing you to new people by forming a coalition around a “friend-group activity”—whether that is a dance challenge, wisecracking or whatever.

13. TikTok's parent company is Chinese Internet behemoth ByteDance, a $75b company that bills its self as an artificial-intelligence company, NOT social media.

14. TikTok purchased Musical.ly (which had grown to an audience of 100m) in December 2017, in a deal reportedly worth $1b, and merged it with the existing TikTok database of 500m+ worldwide by August 2018. The upgraded TikTok app incorporates the most popular elements of TikTok and Musical.ly apps

15. “Combining Musical.ly and TikTok is a natural fit given the shared mission of both experiences—to create a community where everyone can be a creator,” Alex Zhu, co-founder of Musical.ly and senior VP of TikTok, said in a statement at the time.

16. If there’s one way to describe the app, its ENGAGEMENT. Bytedance is using the theory of just showing people content to get them to engage, then using powerful AI, watching what the audience does with what they are shown and take copious notes to make future suggestions, inducing a content wormhole that is, well, engaging.

17. Google already watches what you do and makes guesses about who you are—that’s why you can get content recommendations on YouTube without following a single account.

18. The keywords here: artificial intelligence.

19. TikTok’s fundamental influence is that its questioning the individual connections and friend networks and embraces central control—a trend that other social media networks are in the process of following.

20. TikTok is based in Los Angeles, with offices all over the world: London, Tokyo, Seoul, Shanghai, Beijing, Singapore, Jakarta, Mumbai and Moscow.

If you didn't know before, you do now.