"Big Soviet Encyclopedia" (SI) is a publication that has become a real treasure of knowledge for Soviet society. In terms of volume and variety of information, it surpassed all previous encyclopedias and became an integral part of every family's home library. This encyclopedia contains history, culture, science, technology, geography and many other useful and interesting information. Each article was written by professionals in their field and contained the most current information at the time of writing. "Big Soviet Encyclopedia" (SI) became an absolute reference for schoolchildren, students, teachers and all those who were interested in the world around them.