There are two types of volcano, composite and shield.
Composite volcanoes are steep-sided and cone-shaped, made up of layers of ash and lava and containing sticky lava which doesn't flow very far.
Mount Etna in Italy is a composite volcano.
Shield volcanoes have gently sloping sides and runny lava that covers a wide area. Gases escape very easily from shield volcanoes.
Mauna Loa in Hawaii is a shield volcano.
Composite volcanoes are steep and made from layers of ash and lava