I use single quotes when the string in question is used like an enumeration: set_color('black','white') And double quotes for strings meant to be read by

I use single quotes when the string in question is used like an enumeration: set_color('black','white') And double quotes for strings meant to be read by a human: print("Hello there. How are you?") And an example with both forms: syslog('warning',"unit %s spin rate %f too low",u,rate) For me, it's an indication of how I expect the string to be used.