[General Topics] TheMystic:
Some of the things that BIG TECH (Google, Facebook, Apple, Microsoft, Amazon, and others) uses to identify you:

1. IP address

2. Browser Fingerprinting

3. Device Fingerprinting

4. Location, Nearby scanning, Beams, GPS

5. Advertiser ID

6. Always Listening (voice commands)

7. Your demographic details

IP address

This is the same for all devices connected to the same WiFi network. This address is called the Public IP address, which is the address assigned to your WiFi router by your ISP. Using this, Big Tech can track all the accounts that use the same IP address. So, Big Tech knows who all are living in the same household, who all are working in the same place (if you connect to your work WiFi), etc.

Browser Fingerprinting

Websites can track full details of your browser, which in conjunction with other forms of tracking (like cookies), can be used to create your virtual profile, your interests, your online activities, etc. Google, Facebook, Amazon, etc, have trackers in pretty much all the websites, so even if you don't use your account in those sites, BIG TECH can still track you by connecting the dots.

Using Private/ Incognito browsing isn't all that private as one is made to believe.

Device Fingerprinting

This is similar to, but more advanced form of tracking compared to Browser Fingerprinting. They record details of your device like make, model, display resolution, operating system, time zone, GPS, sensor data, Information About Things Near Device (i.e Wi-Fi Access Points, Cell Towers, Bluetooth-enabled Devices, etc.).

You can change your browser, network, location, etc. But you are unlikely to change your device as frequently. You can be easily tracked using Device Fingerprinting.

Location/ Nearby Scanning/ WiFi/ Low Energy Bluetooth/ GPS

You can change your physical location, but it is highly likely that you will move with your family. So even if you use completely new accounts, they can still track you through your family members' accounts. That's how Facebook recommends same 'Friends' to you even if you use a new account.

Your device is constantly communicating with the tech around you - mobile towers, WiFi routers, Bluetooth devices, GPS, etc. That setting of 'Scanning Always Available' under Location Settings helps in improving this accuracy.

A new technology is in works that will allow tracking of your device even when it is switched OFF! Spyware is essentially being installed at the hardware level and your devices would be under surveillance 24x7.

Advertiser ID

As the name suggests, this is your Virtual Identity containing your interests, online activity history, etc that is provided to advertisers (even if anonymously) for targeted advertising.

You CAN reset this ID on all devices (Android, iOS, Windows, macOS, etc.) to reduce the amount of information advertisers know about you (even if anonymously).

Always Listening

The most privacy disrespecting feature. Your gadgets are constantly listening to you, waiting for your commands. All your personal conversations are recorded. Next feature will be Always Watching! They will develop some interesting application for this feature (like they did for identifying the music around you) and sell you devices that is constantly recording you using cameras!

Your Demographics

Name, Phone number, Date of Birth, Gender, and other details that you provide when creating your account. They have pretty much made it mandatory to give correct information without which you cannot create an account.

Your personal details, contacts, meta data of pictures and videos on your device, etc everything will be linked to identify you from your virtual identity.

CONCLUSION

No matter how hard one tries, he will leave several footprints about himself if using tech. The only way to avoid tracking is to completely give up on use of gadgets and communication devices. VPNs/ TOR Network won't protect you.

FUN FACT

ALL BIG TECH companies, including chip makers are American companies!

Software: Google, Apple, Microsoft, etc.

Hardware: Qualcomm, Intel, AMD, Apple, etc.

Social media: Facebook, Instagram, YouTube, Twitter, etc.

Streaming Services: Amazon, Netflix, etc.

News channels too (there are no journalists anymore; only media-persons)

....you name it: all are American companies! This isn't a mere coincidence!

So you know where all the data goes! And who does all the spying!