The news that Yahoo was shutting down Yahoo Groups, as I said, was another gut punch when you realize how much of the web’s history is so ephemeral. It also got me thinking that Yahoo as a company might be about to go down the memory hole, and that got me thinking about Yahoo’s legacy as perhaps the first great Internet company, and that got me talking to one of the deans of tech journalism, Harry McCracken. What IS Yahoo’s legacy? Why has it ended up the way it has? And also, why do we feel nostalgic for the sort of web Yahoo Groups represents? What has changed on the Internet from the Yahoo Groups glory days until now?