Erno "Emppu" Matti Juhani Vuorinen (born 24 June 1978 in Kitee, Finland) is a Finnish guitarist, mostly famous as one of the founding members, and partly song writer, of the symphonic power metal band Nightwish. He started to play guitar as a private study at the age of 12 and since then he has played in various bands including Nightwish, of which he is a founding member, Brother Firetribe, Almah(With Angra's frontman Edu Falaschi) and Altaria.
Emppu most often supports the keyboard or orchestral parts of Nightwish songs, Marco Hietala easing back to allow the higher pitched guitar of Emppu to take precedence. Vuorinen's solo techniques include short range tapping and minor to extreme whammy bar use for vibrato. His solos are usually more melodically oriented than in many other Heavy Metal bands, such as Children of Bodom, but he can also shred(most notable in the solo in "Nightquest", and the end of "The Pharaoh Sails To Orion".). Emppu is also the only member of Nightwish's current lineup never to have contributed any vocals.
Vuorinen is also involved with a Brazilian metal band called Almah, which he recorded the guitar parts in order to help his friend and vocalist Edu Falaschi (Vocalist of the popular metal band Angra), but instead of staying in the band, he had to leave because he was too busy in Nightwish.
Vuorinen is often referred to as "The short one" when amongst Nightwish members, as well as his other projects, standing at only 5'3" (160 cm) in height. Fans of Nightwish also refer to him as "the hobbit" because of his height.
As of 2008 one of his side-projects Brother Firetribe released their two albums, "False Metal" (Re-released as "Break Out"), and "Heart Full Of Fire" worldwide.