Palo Santo is originally from the coast of South America, it transalates to "Holy Wood", it has a citrusy scent and some sweet notes of pine and mint.
It's ritual purposes trace back to the Inca culture. It's been used for centuries to clean the auric field, helping to get rid of the energy that no longer serves you and to ground yourself. It is also believed that it brings good fortune to the person that burns it. 
Palo Santo has been used for aroma therapy purposes as well, the scent is amazing!