While both dead-end and cul-de-sac imply a street that leads to nowhere, i.e., has no outlet, these differ in how the street in question terminates. Where a dead-end street just terminates abruptly, a cul-de-sac usually has a circular ending that lets vehicles turn around easily without having to maneuver a tricky and often sharp u-turn. In a nutshell, all cul-de-sacs are dead-ends but not vice versa.