; -- suppress the implicit newline after a print-statement
The semicolon (';') may only appear at the last position within a print-statement. It supresses the implicit newline, which yab normally adds after each print-statement.
Put another way: Normally the output of each print-statement appears on a line by itself. If you rather want the output of many print-statements to appear on a single line, you should end the print-statement with a semicolon.
print "Hello ":print "World!"
This example prints Hello World! in a single line.