Because t are sustainable, I can read then any time, & I can take them with me wherever I go. T are not effected by electricity blackouts or computer viruses. When TEOTWAWKI comes due to climate change, I will still be able to read my books. Keith.
The more you complete the book the more enjoyable it will be. So, the book that you will start reading is the one which you should read for a period of time.