Before there was the Internet there were libraries. Your main reference books were dictionaries for looking up proper definitions of unknown words. Then you had encyclopedias for general topics. To get really specialized you had to consult the Reader’s Guide to Periodical Literature. That was an index organized by topic of magazine articles, including scientific ones like Nature. Reference librarians were very helpful in finding specific information in a hurry, and there were some books that couldn’t leave the library.
Before there was the Internet there were libraries. Your main reference books were dictionaries for looking up proper definitions of unknown words. Then you had encyclopedias for general topics. To get really specialized you had to consult the Reader’s Guide to Periodical Literature. That was an index organized by topic of magazine articles, including scientific ones like Nature. Reference librarians were very helpful in finding specific information in a hurry, and there were some books that couldn’t leave the library.