The differences are many and often subtle: use only expects a bareword, require can take a bareword or an expression use is evaluated at compile-time, require at run-time So they behave differently but achieve the same goal. Then there's a list of cultural differences in addition to the technical differences, but they're not so hard and fast.
See also the manuals for details: perldoc -f require perldoc -f use and perldoc perlmod on modules.
The differences are many and often subtle:
use only expects a bareword, require can take a bareword or an expression
use is evaluated at compile-time, require at run-time
So they behave differently but achieve the same goal. Then there's a list of cultural differences in addition to the technical differences, but they're not so hard and fast.
See also the manuals for details:
perldoc -f require
perldoc -f use and
perldoc perlmod on modules.