I
M
A
G
E
C
O
U
R
T
E
S
Y
O
F
F
O
L
D
I
T
.
W
I
K
I
A
.
C
O
M
COMMUNICATIONS OF THE ACM
Departments
5 Editor’s Letter
Moore’s Law and
the Sand-Heap Paradox
By Moshe Y. Vardi
7 From the President
Sometimes It Takes Some Time!
By Vinton G. Cerf
8 Letters to the Editor
Know Your Steganographic Enemy
9 ACM’s 2014 General Election
18 BLOG@CACM
Rethinking How to Teach
Programming to Newcomers
Judy Robertson reviews what
happened when she decided
to introduce Android development
into the curriculum for first-year
computer science students.
43 Calendar
119 Careers
Last Byte
120 Puzzled
A Sort, of Sorts
By Peter Winkler
News
21 How Computers
Are Changing Biology
Sophisticated computer models
and simulations are replacing test
tubes and beakers. This revolution
in biology research is redefining
medicine, agriculture, and more.
By Samuel Greengard
24 The Forever Disc
Can our digital data represent us
a million years from now?
By Tom Geller
27 Technology Confounds the Courts
Despite the need to make decisions
relevant to technologies,
the U.S. Supreme Court is not
the most techno-savvy group.
By Keith Kirkpatrick
Viewpoints
30 Economic and Business Dimensions
Why Bitcoin Has Value
Evaluating the evolving
controversial digital currency.
By Marshall Van Alstyne
33 Law and Technology
What Happened to
Video Game Piracy?
How video games thrive
in a world of piracy.
By Ben Depoorter
35 Historical Reflections
Tom Kilburn: A Tale
of Five Computers
Reflections on a British computer
engineer who influenced several
important machines, including the
first stored-program computer.
By David Anderson
39 Education
Building a Virtual Community
of Practice for K– 12 CS Teachers
Bringing educators together
and focusing their interests toward
improving computer science
education in high schools.
By Steve Cooper, Shuchi Grover,
and Beth Simon
42 Viewpoint
Robots Are Coming
Considering the societal
implications of the
robotics revolution.
By Ruzena Bajcsy
Association for Computing Machinery
Advancing Computing as a Science & Profession
21