feynman.txt

for loop

A for loop is syntactic sugar for a while loop that keeps an initializing and
incrementing statement together with the test so they don't get lost.

&& || !

Boolean operators take Boolean arguments and return Boolean values.  These are
just like functions except the syntax is easier on the eyes.  People sometimes
use truth tables to describe Boolean operations, so here is one.

    x  |  y  || x && y | x || y |  !x  |
    F  |  F  ||   F    |   F    |  T   |
    F  |  T  ||   F    |   T    |  T   |
    T  |  F  ||   F    |   T    |  F   |
    T  |  T  ||   T    |   T    |  F   |

Array

An Array is a structure that aggregates multiple values so that they can be
handled using a single name, or variable.  You can get at the individual
elements of an Array using array subscript notation.  Also, Arrays are objects
that come with some convenient properties and methods, such as .length
and .indexOf.  These are listed on MDN somewhere.

git

git is a version control system that has almost entirely supplanted an older
system cleverly named Subversion.  The history of the text maintained in a git
repository (which is usually source code) is represented as a directed acyclic
graph of commits.  As is typical in a dag, this history has a lot of branching
and merging.  In version control, these indicate paths of mostly-independent
development, possibly under the care of entirely different people.  The
ability to branch and remerge makes git extremely useful in collaborative
software development, and a considerably useful tool for organization even
while working solo.

Github

Github is a site that wraps a collection of git repositories, enhancing them
with issue tracking and discussion and generally making it very easy to copy
(which they call "fork") a project and perform git operations on it.  The
Github notions of forks and pull requests are somewhat analogous to the
simpler branch and merge operations of git, but they operate at the social
level rather than the level of a single repository.