Concrete Paver Sealer is an acrylic or siloxane based sealer. It is usually water-based, but is available in solvent-based forms too. They can be penetrating and invisible, or film-forming and aesthetic.
Acrylic is a fairly durable, UV stable agent that bonds to the surface of the pavers as well as filling a majority of the small pores that exist. These sealers typically last between 2-5 years.
Siloxane is a penetrating release agent that also fills the concrete pores, but does not bond to the surface as the acrylics do. These can last as long as 10 years but do not provide the surface erosion protection of film-forming sealers.
No matter which sealer you choose, you are protecting your pavers so they look great for years to come!