Communication books are generally developed through use and need. Sometimes unfamiliar vocabulary is deliberately included. The communication partner will then be able to model the use of this vocabulary, and the AAC speaker will learn the symbols by seeing them used in practice. Communication books usually develop to include pages of vocabulary related to: about me; people; feelings; clothes; food; drink; animals; colours; numbers; letters; hobbies and interests (whether train spotting or Star Wars); curriculum-related vocabulary. Later, more topics are added such as weather, places, activities, or adjectives – and more words/symbols are added to each topic.