Irish dance (typically the top half of dancers graded after the first two rounds) of dancers are invited back to perform. The Céilí dances used in competitions are more precise versions of those danced in less formal settings. There is a list of 30 Céilí dances which have been standardised and published in An Coimisiún's "Ar Rinncidhe Foirne" as examples of typical Irish folk dances; these are called the "book" dances by competitive stepdancers. Most Irish dancing competitions only ask for a short piece of any given dance, in the interests of time. There are two types of shoes; soft shoes (also
Types of volcanic eruptions Types of volcanic eruptions Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series. There are three different types of eruptions. The most well-observed are magmatic eruptions, which involve the decompression of gas within magma that