Instruction An
instruction tells the computer what to do, but it is very low-level. Unlike source code, it works at the microprocessor level telling the
computer what elementary steps to take to execute the program.
Source code this is the code that the programmer
writes in a high-level language like Java, BASIC, or, in this case, C.
A high-level language is one that humans can easily read and
understand.
Execute To execute the program means to run it. The two terms can be used
interchangeably. To execute an instruction means to do it. It is the process of seeing what the
instruction is, and then doing it.
Jump A jump occurs when the computer is told to start
executing instructions somewhere else besides
the next instruction after the current one being executed.
Program counter The instructions are stored as a
sequence of numbers in the computer just like anything else.
The computer usually executes one instruction after another unless it
is told to jump somewhere
else. The program counter keeps track
of what instruction in memory is being executed at any given time.
Subroutine Good programmers break theyre program up
into smaller steps called subroutines.
A program to make coffee could be
broken up into preparing the filter, putting water in the coffee maker, and turning the coffee maker on. Each of these subroutines can be broken
down into more subroutines. Putting water in the coffee maker could be
broken down into get a cup, turn on the sink, put the cup under the sink, turn off the sink when the
cup is full