SANITISE
Sanitise the input from a user for example so not to expose yourself to things like XSS.
Example
DEF content$=SANITISE("<script>alert('XSS')</script>")
PRINT content$
LINE BREAK
PRINT SANITISE("<script>alert('XSS')</script>")
Output
<script>alert('XSS')</script>
<script>alert('XSS')</script>
<script>alert('XSS')</script>