Hardware Reference
In-Depth Information
stage
Refers to the background for the sprites in Scratch. You can add scripts to
the stage to allow the sprites to interact with it—for example, you might draw
a wall that stops your sprite from moving beyond a certain point.
string
Data or information entered as text, i.e., a “string” of characters.
sudo
The
sudo
command lets you temporarily act as the
super user
(or
root
user)
and gives you permission to do whatever you want on the system.
syntax
A set of rules to check whether the code you have typed is valid code. In
the same way as the English language has rules about how to properly combine
subjects, verbs, objects and so on, each programming language has its own
syntax.
syntax error
An error that stops a program from running because the computer
cannot understand the code.
terminal
A screen window that gives you access to the command-line interface.
The graphical LXTerminal is an example.
threads
A way to run more than one script simultaneously.
turtle
An imaginary pen used to create graphic images using a sequence of
instructions in the Turtle Graphics program.
uinput
A special hardware driver that allows other programs to inject keypresses
into the system as if you had pressed a real key on the keyboard. It is a special
kernel driver that has to be installed inside the Linux kernel in order to do its
work.
USB (Universal Serial Bus) port
A type of opening on a computer used to plug in
devices such as a webcam, or a portable memory device like a memory stick.
variable
A code construct that holds a value that can be changed. The
health
variable in your adventure role-playing game in Adventure 3 is an example of a
value that can be changed and used inside different scripts.
voltage
The difference in electrical energy between two points in a circuit. It is the
electrical equivalent of water pressure in pipes, and it is this pressure that
causes a current to flow through a circuit. Voltage is measured in volts (V).