On the Internet, some sites outside the U.S. use the compound designation milliard/billion to designate the number 1 000 000 000. In science, the names of large numbers are usually avoided completely by using the appropriate SI prefixes. Thus 10 9 watts is a gigawatt and 10 12 joules is a terajoule.
Blood thinners like warfarin (Coumadin) can make you bleed more easily -- including from your gums. Some anti-seizure, blood pressure, and immune-suppressing drugs make the gums grow too quickly. The new gum tissue is more delicate and may bleed when you brush it.
There are also other reasons for gum discoloration that cause a higher concern. First is acute necrotizing periodontal disease, also referred to as black gum disease. This black discoloration of the gums is due to dead tissue, or necrosis. This is a serious health issue, with symptoms that can also include bleeding gums, strong pain, and a foul smelling mouth. Along with improper oral care, the causes of this disease can include stress, smoking, viral infections, and HIV.