The Internet is not Forever
It used to be (and may still be?) the received wisdom that “the Internet is forever”, meaning that once something is on the Internet, it will exist forever. If this was ever true, it no longer is. Off the top of my head, there are five ways that things disappear.
Link rot. Maybe you saw something you wanted to remember and you even bookmarked it. But, the site owner restructured the site, or moved to a new CMS. Even if you have a previously working link, you may never be able to find the item again.
Search results change. Perhaps you have something that you found through a web search. You didn’t save the link, but you just type a couple of keywords into the box and pull up the third result. It’s really easy to lose something then. Search engine algorithms are constantly changing. The Internet those algorithms are indexing is changing even faster. You can’t count on finding a particular result through a search engine.
Social media shows content algorithmically. When it comes to algorithm-related content disappearance, social media is the worst. To take Twitter/X as an example, what most people would prefer from their feed is a chronologically sorted display of posts from the accounts the user follows. What the user gets is an algorithmically sorted display of posts from a mix of accounts and advertisers related to the kinds of accounts the user follows. This means, if you remember seeing something interesting a couple hours ago, but you didn’t save it, you are unlikely to see it or be able to find it again.
Things get taken down. Sometimes, whether malicious or legal, third parties act to get items removed from the Internet. Maybe that video you wanted to see again accidentally had a clip of copyrighted music in the background. The music studio algorithm hears it and has a conversation with the video site’s algorithm and the video disappears. Maybe somebody has a botnet and wants to disrupt the CDN that serves the page you’re looking for. Maybe some network engineer is having a bad day, misconfigures some BGP routing, and turns off the Internet for your country. These things happen.
Things get deleted. Sometimes who ever posted something just wants remove it. If no one saved a copy somewhere else on the Internet, then it is gone. This kind of points to the nugget of truth in the idea of the Internet’s forever-ness. Anything on the Internet can, in principle, be copied and reposted. What matters is what people are willing to do that for. Murphy’s Law indicates that what gets widely distributed is what the poster would most prefer to remove from the Internet.
The Internet is not forever. Save the things that are important to you. Maybe look into IPFS and support the Internet Archive, too.