GPS Made Easy: Using Global Positioning Systems in the Outdoors. 4th ed.

Charles R. Crawford, a former associate professor of computer science at
York University, is a computer programming and mathematics consultant in
Toronto.

The Global Positioning System operates under the auspices of the U.S.
Department of Defense, and includes several satellites and ground-based
computer systems. With a GPS receiver, you can determine your position
on earth with an accuracy of 15 metres using an older model and five
metres using the latest receivers. The satellites use ground-based
stations to determine their own positions. The GPS receiver, using the
clocks on the satellites, calculates the difference in time required to
exchange signals with the satellites, and uses the difference and the
satellite’s position to determine its own position.

GPS Made Easy begins with a short history and explanation of GPS, and
follows with a description of typical receivers and what they might be
used for. Next are five detailed examples of how GPS is used; some of
these, such as collecting water samples from springs in a desert area or
navigating on a glacier in a whiteout, are quite complex. Subsequent
chapters discuss using a GPS receiver in a car, with an ordinary
computer, with a laptop, or with a palmtop. The final three chapters
deal with specialized topics. The book includes a glossary of terms, a
bibliography, an index, and a list of websites for further information
about GPS.

This guidebook would be very useful for anyone wishing to buy a GPS
receiver. The writing is clear but not too technical, and the book
focuses on terminology and features rather than brand names and models.
The inclusion of a bit of history and the examples makes it an
interesting as well as a useful guidebook.