For this reason almost all English braille books use a transcription known as "Grade 2 braille". Grade 2 braille uses contractions, which allows to save space and increase reading speed. Grade 2 braille was developed by linguists (people who study languages), who also looked at customs, styles and practices. Transcribing a text into Grade 2 braille is difficult, and the people doing the transcription need to have a special education.