Book excerpt: Alford Books goal is to freely share knowledge worldwide. We teach simple subjects - One Story at a Time. Categories include: Science, Technology, English, Math, Life Skills, History and Cultures. (STEM-LHC, pronounced STEM-Look). There are over 60 English Alford Books available in over 200 International Language versions. Alford Books come in three levels: 1) Easy; 2) Interim; 3) Advanced. As you grow in knowledge and skills, the books grow with you. We appreciate feedback on ways to improve our books. -Douglas and Pakaket Alford