The Science of Computing - A Concise and Practical Introduction to Programming Algorithms in Java - page 222

10.3 The digital equation
Mark Weiser envisioned the era of ubiquitous computing , where computing
devices are omnipresent. We are experiencing more and more this life style
with the Internet and current cell phones. How is it that even if content was
binarized that computing became ubiquitous?
This is because of the digital equation:
Digital = Binary + Calculation
Indeed, consider pictures to illustrate this equation. At first, pictures were
analog. We then digitized them into binary strings using various devices like
photo scanners. But nowadays, we are yet a stage beyond: We have entered
the era of computational photography . That is, photos are computed. You can
buy digital cameras that implement smile shutter or other functionalities that
could not exist in the analog era. The digital equation opened up a completely
unknown world. There is a novel momentum of the media: What is a (digital)
photo and how can we (computationally) capture/manipulate and share them?
Computing not only allows us to experience novel experiences with former
media, it also allows us to create brand new media that were quite unthinkable
in the analog world. For example, within a couple a decades our flat TV will
certainly be for sure replaced by a networked 3D holographic display. This will
be possible not only because of hardware progress but also because a brand new
type of media will be captured and processed: geometry . To simplify, we may
say that the first media era was sound (1970's). Then came images (1980's) and
videos (1990's). The 21st century (2000) with the rise of geometry processing
will be about geometries (improperly called 3D videos). And who knows, this
digital equation could also be one of the hidden laws of Nature.
10.4 Birth of algorithms and computers
The birth of algorithms is allegedly credited to Al-Khwarizmi (790-840), a
Persian scholar working in the scientifically flourishing city of Bagdad. Al-
Khwarizmi wrote important scientific treaties and is considered one of the
fathers of algebra (Al jabr). The word “algorithm” stems from the latinization
of “Algorithmi.” Indeed, Al-Khwarizmi was concerned with providing his
readers with generic pipelines to solve for solutions of quadratic equations.
A common misunderstanding is to associate computer science necessarily with
computers. Computer science is not about programming personal computers.
The difference engine, conceived by Charles Babbage in 1822, is one of the very