Phishing.
Its the elephant in the room but we should talk about phishing for a moment. Its an ugly side of the Internet and common as its comes. A good chance exists that if you write something and open it up for comment, one of the commenters will leave along a link that will lead you off to parts undesired.
Why? Why do "they" do stuff like this?
Simply put, the goal of all phishing is to gain access. Access to information, access to credentials, e.g., your username and password; access to accounts ... access, access, access. It might be doctored up with an attachment via email or a link in a chat or comment, but the end result is still the same: they want in.
Don't be fooled by the Call to Action
The phishermen (and we'll get to who "they" are in a bit farther down) are talented in finding ways to elicit information or entice you to take an action of their choice. They play on all the big themes that will lead or sway you to the (wrong) path. Some (not inclusive) interesting Call to Action you might have experienced:
Good Citizen
A play along the theme of "let you voice be heard".
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Curiosity
The "click on this! you'll love it!!!" or "you can beat this" types of phishing.
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Authority
More affectionately called the "we are watching you" theme.
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Emergency
The "you must do this now or suffer consequences" type of threat.
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Or, this one:
Banking
Typified by the "money", "bank account", or "verify account" line of threatening.
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Its Them!
Let's just to the "them". Who are these people? Take another side step with me and change the world Phishing to Marketing. As a primer, Marketing is "the process of planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services to create exchanges that satisfy individual and organizational goals." Phishing, in effect, is the same thing. Just like Sales, the actual selling or delivery is just part of Marketing. The phishermen play a roll just as diverse and required in business as marketers. What they sell is that access we mentioned earlier. Phisherman want to get from you a product (your credentials, or access) and sell it or use it to gain money.
Its people!
The "them" is you. Or, more accurately people like us who do this for a living. Some are overseas, some are in your country, and some might even be next door. Its what they do for a living.
Conclusion
Be alert. Think before you click a link, no matter where its coming from or who sent it. Follow the mantra of, "trust but verify". If the link is to a site you know, especially for an alert or notice, type the url in manually versus following the link. If its a person you know, check with them via another means.