The national language in Ireland is Irish or Gaeilge, however English is the most widely spoken language in the country. While County Clare has no official Gaeltacht area, there are a number of areas (West Clare in particular) where Irish is spoken widely on a daily basis. Reviving the Clare Gaeltacht is the aim of a number of people in the county as they seek official Gaeltacht status for the county. There is an Irish College in Cattigaholt that takes students during the summer time.
Many signposts are in Irish first and then English so take a second to make sure you are going in the right direction. If you feel brave enough learn a "Cúpla Focal" (a few words) and try your hand at having a brief conversation in this beautiful language. The pronunciations can be tough and are very guttural so lots of practice will be needed. It gets easier after a few pints of the black stuff!