Congress recently voted against privacy protections from Internet Service Providers (ISPs). That means, ISPs have a lot more latitude to collect data about your browsing habits, and sell that data to their ad partners. One might think, the only people who are impacted by that vote are those looking at adult material on the internet. That's not the case though.
...When you make a voice call on your smartphone, the information is protected: Your phone company can’t sell the fact that you are calling car dealerships to others who want to sell you a car. But if the same device and the same network are used to contact car dealers through the internet, that information — the same information, in fact — can be captured and sold by the network. To add insult to injury, you pay the network a monthly fee for the privilege of having your information sold to the highest bidder. - Tom Wheeler, Former F.C.C. Chairman, Source: New York Times
Your browsing habits reveal a lot of detailed information about you. For example, if you're searching for cholesterol medication online, your ISP can see that. Accompanied with your name, gender, age, and address, your ISP has some pretty specific knowledge about you and your medical condition. That knowledge is worth money, and can be sold in exchange for money.
The bill not only gives cable companies and wireless providers free rein to do what they like with your browsing history, shopping habits, your location and other information gleaned from your online activity, but it would also prevent the Federal Communications Commission from ever again establishing similar consumer privacy protections. - Tom Wheeler, Former F.C.C. Chairman, Source: New York Times
Private or Incognito browsing might offer some privacy protection from companies like Google, but it offers zero protection from your ISP. This is because, you connect to the internet through your ISP. They see everywhere you visit. They can also see what you're doing on a given website, if your connection is unencrypted. I won't cover encryption in the post. However, an encrypted connection is always better than one that it not. Your connection is encrypted, if you see a padlock in your browser's URL bar. Your connection to this website is encrypted.
What is a VPN?
When you connect to a website, your computer is exchanging information with another computer or server (website) on the internet. Your ISP knows that you and the website you're visiting are talking to each other. As mentioned earlier, if your connection is unencrypted, they can also see the details of the information you're exchanging with the website. A VPN (Virtual Private Network) gets in the way of that.
When using a VPN, your computer establishes an encrypted connection to a VPN provider. Your VPN provider sends your traffic to the website you're visiting. Then, the website sends data like text, photos, and video, back to your VPN provider. Finally, your VPN relays that same information through the secure connection that you share.
Your ISP can see that your connected to a VPN provider, but the rest is generally off limits to them. They can't see any of the traffic exchanged between you and your VPN provider, because it's encrypted. They don't know what websites you're visiting, because the VPN provider is sending traffic from thousands of people to thousands of websites. Also, good VPN providers pledge not to keep any records of customer traffic.
Do I Have Complete Privacy, if I Use a VPN?
No. There's no such thing as total privacy.
If you choose a less reputable VPN provider, they might keep logs of the sites you visit. Instead of sharing your browsing data with your ISP for profit, you'd be sharing it with your VPN provider for their profit. Choosing a VPN vendor is like choosing a contractor. You need to do your homework.
If law enforcement suspects you of conducting illegal activity, they can serve your VPN provider with a warrant. They can also serve your ISP with with a warrant. Most people can avoid this risk by simply not using the internet to commit crimes.
How Do I Find a Good VPN Provider?
That One Privacy Site rates a lot of popular VPN service providers. If wanting to know what criteria they use to rate a provider as green, yellow, or red in any one category, these definitions contain some useful information. A quick Google search will reveal some popular providers that are well regarded by their customers. Good luck, and ask questions.