Bill Callahan (born 1966), also known as Smog and (Smog), is an American singer-songwriter born in Silver Spring, Maryland. Callahan began working in the lo-fi genre of underground rock, with home-made tape-albums recorded on four track tape recorders. Later he began releasing albums with the label Drag City, to which he remains signed today. Callahan started out as a highly experimental artist, using substandard instruments and recording equipment.