Passports
EU nationals entering France need only a national identity card; visitors from the UK should take their passport. In any case, airlines usually ask for passports.
Nationals from other countries must be in possession of a valid national passport.
Visas
There is no requirement for a visa for EU nationals, nor for citizens from the US, Canada or Australia travelling as tourists and staying for less than 90 days, except for students planning to study in France.