Targeted advertising isn't new. Newspapers have long placed adverts where they would have their most effect - recreational equipment for sale on the sports pages, for instance.
What has changed is the amount of information being scraped about you, from your online behaviour.
By opening accounts on these platform, you waive the thin veil of confidentiality you may want to draw over your personal life. Once drawn back, there is no pulling it across again. Your information has passed, in a blink, to the all-seeing eye of technology.
Social media firms now know when you're engaged to be married, pregnant, on holiday, sick or worried about balding. Companies are tracking our online movements to ensure they can put the most relevant advertising in your path - to secure the all-important sale.
It's now estimated you spend an average of six hours a day online, effectively working fulltime, teaching an algorithm how to exploit you.
The major player Facebook has becoming more transparent about the information it compiles about you. Unfortunately, it appears this has largely occurred only after complaints, and exposure by media, into the unannounced incursions into what users had assumed were private matters.
A Washington Post investigation, for instance, revealed Facebook is trying to build a jigsaw of you by compiling 98 specific pieces of information, from your gender and age; what toppings you like on pizza; your political leanings; stance on abortion; sexual proclivities; and whether you're a light or heavy drinker. How many strangers would you usually share this information with?
Google, as the name suggests, is also staring constantly into your life via your searches and browsing history. Not only looking, but storing the details and constructing an avatar of you to be turned into profit.
Information technology has brought many life-enhancing features to our lives. Network coverage saves lives, video calls instantly ease loneliness and emailed images bring genuine happiness in the act of sharing moments. But connectivity has come at a price.
In more recent times, we have partly caught up with some of what Big Tech has been up to, and installed regulated protections in the form of privacy and telecommunications laws.
This week, the NZ Herald embarks on a major, four-part series on social media because we believe you have the right to know what the world is finding out about you - and how you can attempt to protect yourself, if you wish.
Once informed, it's for you to decide whether you still "like" to give so much about yourself away.
