Cachaca is essentially a rum distilled from Cachaca (fermented sugar cane juice - similar to that used to make Rhum Agricole).
It is mainly produced in Brazil, where it is the country's most popular spirit. It is bottled at between 38% and 54% abv. It is legally permissible to add up to six grams of sugar per litre when making Cachaça, and it is most commonly used in the legendary Caipirinha cocktail, the national cocktail of Brazil.
Cachaca is sold unaged and aged. The unaged variant, "white Cachaça", is bottled either immediately after distillation or after no more than a year in wooden barrels. The aged variant, "Gold Cachaça", is regarded as the more Premium style, and is usually aged in wood for around 3 years, though often much more.
The Gold variant is intended for drinking neat, whilst the former, White variant, is best suited for use in mixed drinks, particularly the aforementioned Caipirinha (made with lime juice, sugar and ice).