Ключевые слова: abstract, background, book, business, concept, culture, dictionary, document, education, encyclopedia, green, group, guidebook, heap, ideas, information, isolated, knowledge, learning, literacy, literature, medium, nobody, open, page, paper, pile, publication, read, readers, red, school, space, stack, student, studio, study, studying, text, textbook, university, vertical, white, wisdom, word, workbook,