source lines
Source lines are separated by newline characters, labeled Enter on most keyboards.   Statements and expressions are terminated by the end of source lines.

line names
Source lines can be given names, called labels. Line labels begin in the first character position on a line and are terminated by a : character, as in thisLabel:.  Program execution can be transferred to line labels by GOTO statements, as in GOTO thisLabel.

subroutine names
Subroutines are named sections of functions that can be called from elsewhere in the function. Subroutines begin with SUB SubName and include all lines to the next END SUB statement.  Subroutines are called by GOSUB statements, as in GOSUB SubName.

The ' character begins a comment, except when it forms a valid character constant or appears in a literal string.  The ' and the rest of the source line are taken as a comment and have no affect on program operation, size, or speed.  See character literals and literal strings for the exceptions.

Statements that begin with a variable or array names are assignment statements, and must be followed by an = assignment operator.  typenameAT() statements may also begin assignment statements, and must also be followed by an = assignment operator.  See "Direct Memory Access" for typenameAT().