The Optimist is a small, single-handed sailing dinghy that is internationally the most popular boat for children to learn to sail in. They are great for beginners and small kids, and sailors usually continue to race them up to 15 years of age. 

The Optimist is recognized as an International Class by the International Sailing Federation.

Keel(daggerboard or centreboard)
LOA7 ft 9 in (2.36 m)
LWL7 ft 2 in (2.18 m)
Beam3 ft 8 in (1.12 m)
Draft5 in (130 mm) / 2 ft 9 in (0.84 m)
Hull weight77 lb (35 kg)
Mast height7 ft 5 in (2.26 m)
Mainsail area35 sq ft (3.3 m2)
RYA PN1646
Development LocationInternational