Half-life The
time that it takes for a particular radioactive substance
to decay to half of its original amount.
Half-line A
ray, with or without its endpoint. The half-line is said
to be closed if it includes the endpoint, and open if it
does not include the endpoint.
Half-plane
The part of a plane that lies on one side of a line in the
plane. It is a closed half-plane if the line is included.
It is an open half-plane if the line is not included. The
line is the boundary of the half-plane in either case.
Hamiltonian
Cycle A path that beings at some vertex and then
visits each vertex exactly once, ending up at the original
vertex.
Hamilton's
apportionment plan An apportionment plan in which
the representation of an geographical area is determined
by finding the quotient of the number of people in that
area divided by the total number of people and then the
result is rounded as follows: Allocate the remainder, one
at a time, to districts on the basis of the decreasing order
of the decimal portion of the quotients. This method is
sometimes called the method of the largest fractions.
Hare Method
Each voter votes for one candidate. If a candidate receives
a majority of the votes, that candidate is declared to be
a first-round winner. If no candidate receives a
majority of the votes, then with the Hare method,
also known as the plurality with an elimination runoff
method, then the candidate(s) with the fewest number
of first place votes is (are) eliminated. Each voter votes
for one candidate in the second round. If a candidate receives
a majority, that candidate is declared to be a second round
winner. If no candidate receives a majority if the second-round
votes, then eliminates the candidate(s) with the fewest
number of votes is (are) eliminated. Repeat this process
until a candidate receives a majority.
Hamiltonian
cycle A path that begins at some vertex and then
visits each vertex exactly once, ending up at the original
vertex.
Hard copy
The output produced on paper by a printer.
Hard disk
A secondary storage device often installed inside the main
component. A hard disk is used to store the programs one
usually uses, as well as any necessary data.
Hard drive
That part of a computer on which data can be stored by the
operator.
Hardware The
physical components (mechanical, magnetic, electronic) of
a computer system.
Hecto- A prefix
meaning 100.
Heptagon A polygon
having seven sides.
Hexagon A polygon
having six sides.
HH method
See Huntington-Hill's plan
Higher-level
language A computer programming language (e.g.,
BASIC, PASCAL, LOGO) that approaches the syntax of English
and is easier both to use and to learn than machine language.
It is also not system-dependent.
Hindu-Arabic
numerals Same as the usual decimal numeration system
that is in everyday use.
Horizontal
ellipse An ellipse whose major axis is horizontal.
Horizontal
hyperbola A hyperbola whose transverse axis is horizontal.
Horizontal line
A line with zero slope. Its equation has the form y = constant.
Hundred Ten 10s.
Huntington-Hill
An apportionment plan currently in use by the U.S. legislature.
It is based on the geometric mean of two numbers, a and
b, where a is the value of the exact ratio rounded down
and b is the value of the exact ratio rounded up. It rounds
down if the exact quota is less than the geometric mean
and rounds up if it is greater than the geometric mean.
Hyperbola The
set of all points in a plane such that, for each point on
the hyperbola, the difference of its distances from two
fixed points (called the foci) is a constant.
Hyperbolic
geometry A non-Euclidean geometry in which a Saccheri
quadrilateral is constructed with summit angles acute.
Hypotenuse
The longest side in a right triangle
Hypothesis
An assumed proposition used as a premise in proving something
else.
