A lot of websites put cookies on your computer in order to save information about your previous visits to the site. The most common use case would be storing a key that would allow your computer to auto-login to the site the next time you visited it (rather than forcing you to re-login).
Many sites also put cookies on your computer to figure out if you’ve visited the site before, and may change behavior based on whether you’re a new user, or you’re a returning user.
For example, take a look at this website. Let’s ignore the product that it’s advertising for now and just focus on the “Limited Time Savings” offer on the right side. Isn’t it strange how the timer started at 5:00 exactly? In other words, either you were incredibly lucky to have visited the site exactly 5 minutes before the offer ended, or there’s some other trick they’re pulling.
It turns out that one of the cookies (I haven’t looked into it enough, but if you poke around, you should be able to find it) they store on your machine determines when this limited time offer either started or expires. What it means is that the first time you visit the site, the cookie is created and you have 5 minutes from that moment to do this purchase. Afterwards, the cookie still exists on your computer, so it won’t offer you the deal anymore.
But this means that if you get rid of the cookie, you can get the 5 minute deal back. If you get an extension such as EditThisCookie that’s able to view and manipulate cookies, then you can have a lot better control of what websites are storing on your computer.
Some other websites this trick works on include LinkedIn and Quora, which ask you to create an account to view content after the first time you visit their site. If you don’t want to create an account, then simply delete any cookies they’ve stored on your computer and you will be able to access the site as if it was your first time.
That’s all. Thanks for reading!