A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption. They are sometimes confused with volcanic craters. The word comes from Spanish caldera, and this from Latin CALDARIA, meaning "cooking pot." In some texts the English term cauldron is also used.

In 1815, the German geologist Leopold von Buch visited the Las Cañadas caldera of Teide on Tenerife, and the Caldera de Taburiente on La Palma, both in the Canary Islands. When he published his memoirs he introduced the term caldera into the geological vocabulary.

A collapse is triggered by the emptying of the magma chamber beneath the volcano, usually as the result of a large volcanic eruption. If enough magma is ejected, the emptied chamber is unable to support the weight of the volcanic edifice above it. A roughly circular fracture, the ring fault, develops around the edge of the chamber. Ring fractures serve as feeders for fault intrusions which are also known as ring dykes. Secondary volcanic vents may form above the ring fracture. As the magma chamber empties, the center of the volcano within the ring fracture begins to collapse. The collapse may occur as the result of a single cataclysmic eruption, or it may occur in stages as the result of a series of eruptions. The total area that collapses may be hundreds or thousands of square kilometers.

Junior Caldera is a French disc jockey from Paris. A multi-instrumentalist, Caldera was influenced by many musical styles and made rock music before becoming involved in house music in 2002 whilst working as a stage designer in a number of Parisian nightclubs. To date, he has released one studio album and three official singles, two of which have reached the top 40 of the French singles chart. Aside from his solo career, Caldera has produced remixes for a number of musicians, such as Paulina Rubio and Enrique Iglesias.

Following his move into electronic music in 2002, Caldera was given a residency at D! Club in Lausanne and in 2003 he won a mixing contest and was awarded to opportunity to warm up for David Guetta. He later moved on to electronic dance music and in 2007, his track "Sexy" became popular in many French clubs, reaching the top 5 of the French Club Charts. Following this success, Caldera was invited to remix tracks by various notable artists, including the Pussycat Dolls, Enrique Iglesias and Paul Van Dyk.