"FEWER" and "LESS"

"Fewer" is used for countable items. "Less" is used for uncountable quantities. Ex.: We need fewer chairs. There is less water in the bottle.

"DISCREET" and "DISCRETE"

"Discreet" means careful or unobtrusive. "Discrete" means separate or distinct. Ex.: She was discreet about her personal life. The project was divided into discrete tasks.