Millions of sites appear and disappear on the Internet every day. Portals go to the “other world” for various reasons. Sometimes the sites are closed by Roskomnadzor together with law enforcement agencies. This happens when the portal pages contain information that is prohibited for distribution in the Russian Federation (drug and suicide propaganda, extremism, child pornography, pirated content). The domain owners are notified of the decision by the provider. The case materials can be found on a special state website. Roskomnadzor’s blocking can be bypassed with the help of appropriate programs or proxy servers. The prohibitions of Russian authorities do not apply to residents of foreign countries. Commercial Internet projects are not always successful. The creators of the site should regularly pay for the domain name, hosting and advertising. If the revenues that the site brings fall, then the business ceases to pay for itself. The portal in this case needs to be closed so that it does not generate losses. Sometimes a domain name is sold to a new owner, who radically changes the subject of the site. Sites are periodically attacked by hackers. They can infect portal pages with a virus or launch a DDoS attack. In this case, the user will see the message "Error 404". This figure is familiar to the entire online community. It means that the server cannot process the user’s request. The site may be closed for reconstruction. After the "overhaul" you will see a new design and additional features. A notification of “repair work” usually appears on the main page in advance. Portals may be temporarily unavailable due to technical problems on the servers. Usually this phenomenon is temporary. System administrators quickly fix problems and restart the system. Some sites become "ownerless." Their creators stop uploading new content to the site and pay for advertising. Portals are left unattended and closed by providers. The Internet is like a large organism that consists of cell sites. In the body of humans and animals, the cell base is constantly being updated. Old cells die, and new ones are born. Thanks to this, the body grows, develops and gets rid of pathogens. The network is developing largely due to "website traffic."