Tandems are a very useful piece of gear.
Two experienced cyclists can go for a ride and really get some speed up.
One experienced and one not so experienced cyclist (or even non rider) can ride one over long distances and do so safely.
Or they can be used to go and collect someone from a distance place and then ride back with them.
They are NOT suitable for two inexperienced cyclists as there are two people braking and turning at the same time, so some care should be exercised with this bike.
Helmet, lock and basket included.