An e-reader, also called an e-book reader or e-book device, is a mobile electronic device that is designed primarily for the purpose of reading e-books and digital periodicals. An e-reader is similar in form, but more limited in purpose than a tablet.-book reading is increasing in the US; by 2014 28% of adults had read an e-book, compared to 23% in 2013.
Fields relating to the environment: 1  Aerobiology (pronunciation) â The study of airborne organic particles.  Astrobiology (pronunciation) â The branch of biology concerned with the effects of outer space on living organisms and with the search for extraterrestrial life.
The biological fields of botany, zoology, and medicine date back to early periods of civilization, while microbiology was introduced in the 17th century with the invention of the microscope. However, it was not until the 19th century that biology became a unified science.