169 7. Omit spaces wherever possible – but you must keep a space or a % or sign or some other separator before most keywords to avoid ambiguity. If a variable FRED is in use then you must write Y=FRED OR MARY and not Y=FREDORMARY In the latter case the computer will look for the variable FREDORMARY rather than the two variables FRED and MARY . The space after OR is not required. 8. Omit REM statements. 9. Remember that the whole of user memory can be kept for use by your programs by using the ‘shadow screen’ facility – see chapter 42 for more details.