My kids will never know a time before the World Wide Web. I was already in university when the web arrived, so I have many memories of doing things that I no longer do as a result of this communications revolution. Here are some things that the web has replaced.
Encyclopedias - I think everyone over the age of 30 remembers the encyclopedia as the definitive reference point. It's where I'd start when doing an assignment or writing an essay. The thing about encyclopedias was that they were heavy and expensive and out of date so quickly. Furthermore, you could read them at the library, but you couldn't take them out. The web means I don't even think about encyclopedias any more.
Maps - I remember those big maps that were impossible to fold. You had to have one to plan your route, and you needed a Perly's or MapBook for driving directions. Now, it's all Google Maps for me and the paper map you buy in stores may rest in peace.
Letters - Remember when you had to write a letter, put it in an envelope, slap an address and stamp on it and drop it in a mailbox? My friend spent a year in Sweden and we communicated in this archaic fashion. That wouldn't happen today, we'd keep in touch via email.
Reference Books - It's not just encyclopedias. I used to have one book with info on movies, another with info on rock bands and others with baseball statistics, hockey players, not to mention the good ol' dictionary. IMDB killed the movie book, AllMusic killed my rock band anthology and BaseballReference and HockeyDB killed my sports stats books.
I'm sure there's more, but these are a few things that the web has replaced. Oh yeah, throw the fax machine in there. Who's faxing anymore?