Dark pattern

Bait-and-switch is a trick used to sell things. First, a company advertises a product at a very low price or says it is free, This is the bait, When the customer tries to buy it, they find out the product is not available. The company then tries to sell them a different product that costs more money or is not as good. This is the switch.^[4][5]

Drip pricing is a trick where a company hides the full cost of a product until the very end, The company shows a very low price at first to get the customer to start buying, the customer clicks through the pages, the company slowly adds extra fees, taxes, or charges that were not mentioned before, By the time the customer sees the real total price, they have already spent a lot of time and effort.

Confirmshaming is a trick that uses shame to make people act. For example, a website might write the "no" button for a newsletter in a way that insults the user. This makes the user feel bad so they will click "yes" instead. A common example is a button that says "No thanks, I like paying full price" to trick people into giving their email address.^[5]

Misdirection can show a large "I accept" button to make a user agree to a program they did not ask for. Because most people click "accept" quickly without reading, they accidentally install a second program by mistake. This trick uses a person's habit of clicking buttons to install things they do not want.^[6][7]

Privacy Zuckering is a trick that makes people share more personal information than they meant to. It is named after Mark Zuckerberg, the person who started Facebook. Websites use this trick by making it hard to find the "no" button or by hiding the settings that keep your information private.^[8] This leads people to give away their data without knowing it.

A roach motel is a design that makes it very easy to sign up for a service but very hard to leave. For example, a company might let you join a website with one click, but force you to print and mail a letter just to cancel your account^[9].^[10] The goal is to keep charging the user money by making it too difficult for them to quit.