miji.beA URL is not just the address of a web page. If you look closely, all kinds of secrets are planted in it, from developers' playfulness and hidden corporate messages to, at times, even declarations of love.
First, let's look at the world of jokes that developers plant in URLs. Websites have a "404 error page" that is displayed when you access a page that does not exist. There is a culture of planting jokes in the 404 page itself. On GitHub, when you access `github.com/404`, an animation of the Octocat floating in outer space is displayed. Pixar at one time displayed, at `pixar.com/404`, an image of the character "Sadness" from the movie "Inside Out" crying. It is a touch that expresses the sadness of "the page could not be found" through a character. On Lego's 404 page, the notice "Page not found" comes with wordplay based on the head of a Lego figure.
The technique of embedding meaningful words in a URL path (slug) is called a "vanity URL." In corporate marketing, using meaningful words in campaign URLs creates links that are easy to remember and easy to spread by word of mouth. For example, when Apple announces a new product, it uses a simple, easy-to-remember URL such as `apple.com/iphone`. However, the uses of vanity URLs are not limited to marketing. Another use is to create a short URL like `bit.ly/i-love-you` and redirect it to a surprise page for a partner. One could also imagine creating a short URL for a marriage proposal and putting a QR code in the ring box.
There are also examples of companies planting hidden messages in URLs. For example, on one car manufacturer's website, a string made of the initials of model names was used in a URL path. Google's services also hide jokes for developers. When you access `google.com/teapot`, a joke page for HTTP 418 "I'm a teapot" is displayed. This is a traditional internet joke that comes from an April Fools' Day RFC from 1998.
There are also more elaborate examples of hiding information in URLs. Methods of slipping secret messages into everyday communication have existed for a long time, and today URLs can also become a container for them. As a type of steganography (information hiding technique), techniques for slipping messages into URL parameters are being researched. For example, the `ref` parameter in `example.com/page?ref=SGVsbG8gV29ybGQ` is "Hello World" encoded in Base64. At first glance it looks like an ordinary tracking parameter, but in fact a secret message is hidden in it. This technique is being researched as a means of communication in countries with strict censorship, and by hiding information in URLs, "something everyone uses every day," it may be able to escape the eyes of censorship systems. Besides being addresses, URLs contain all kinds of stories.