Palo Santo is often known as Holy Wood and is from the same family of trees as Frankincense and Myrrh. It is rare and very highly valued in the Western world where it is difficult to obtain.
The bark and oil from the Palo Santo tree are so highly prized that it is traditionally burned in South America for the purpose of clearing negative energies from living spaces.
Both the chips and sticks are burnt for meditative purposes and are highly aromatic. the aroma is quite divine (especially of you like frankincense)
The oil is now being used in cosmetics and is being investigated and researched for relief from rheumatic pain.
These wood chips are seen, by some, as easier to burn on charcoal disks than the sticks and give more control over the quantity you wish to use at any one time. They are considered as more convenient in the modern world.