Today was a big today for tech stock lovers, volatility hits the market. So here is a summary of what happened today.Snap and Facebook: rivalry warms upSnap's business model had been questionable even before Facebook released news masks and other stories features. It was a great step forward (from the business standpoint) for Facebook to copy the stories in Instagram, but I still have some doubts about the stories in the messenger. Why should I create the stories when I want to message somebody? I do not want Facebook to force me to create short videos and share them in the messenger but it keeps doing so. Coming back to the subject of copying stories features - it's better for Facebook to focus on Instagram or give an option to turn-off stories inside the messenger. I can imagine stories inside the messenger being big because Zuckerberg follows his aims in a very proper way, there is no doubt that their competition is just warming up. Tencent's investment into TeslaFirst, Tesla is a pure story stock. Second, it has an unlimited credit of trust from the investors. Tencent's 5% stake doesn't mean that the company is going to reach breakeven soon, moreover their production goals are still too high. Investors forced Tesla's management to shut down the production of one of the models, it's definitely a smart move. Don't have an intention to buy the stock when it's so high.Twitter and PeriscopeTwitter is working on TwitDeck now, but today the company announced that users will see the ads before the each video on Periscope. This is not the way Periscope should monetize their audience. Twitter's management needs to check what NHL is doing right now: native video advertising is already working. Just use the same technology, just copy it as Facebook copies Snapchat. As soon as you do, video advertising wouldn't be a problem and Twitter will get another revenue stream.Share some worth reading news from the tech field in the comments below!