Every individual and organization has a carbon footprint. This is the amount of greenhouse gases (GHGs) released annually.
A person or thing is carbon neutral when it does not add greenhouse gases (GHGs) to the atmosphere. Carbon neutrality means being net-neutral -- the entity still emits some GHGs, but it takes responsibility for its carbon footprint and cleans up its “carbon trash.” How? It invests financially in projects that soak up the same amount it emits. For example, a tree-planting project or a landfill methane-capture project.
Anything can be carbon neutral -- an individual, a household, a company, a specific product that a company makes, a city, a state, a country, even the entire world.