Rosemary (Rosmarinus officinalis) is a very popular shrubby, evergreen herb. Its small, drought-resistant leaves are widely used for their various medicinal properties as well as to season food. They are highly aromatic, which means they contain high concentrations of essential/volatile oils, hence their wide use for flavouring food and also as an airborne substance.

Rosemary was originally cultivated on the shores of the Mediterranean. In fact, the herb's Latin name, rosmarinus, is derived from the words "ros", which is translated to dew, and "marinus", which means sea, as Rosemary can survive on just the spray in the sea air. It is a plant well suited to growing in poor or sandy soil, high salt, high wind areas such as the conditions found by the sea.

Rosemary's symbolic uses are deeply inlaid within many cultural traditions including weddings, funerals, and during religious ceremonies. The herb is seen by many as a gift by the gods and as a symbol of love, friendship, and trust. In modern times rosemary is grown throughout the world and is widely used as a medicinal herb and to season food.

Rosemary is a member of the Mint family (Lamiaceae). The first records of rosemary's use as a medicinal herb date back to ancient times in the civilizations surrounding the Mediterranean Sea. The herb was thought to have strong effects on memory and in strengthening the mind. Later accounts include that of Queen Elisabeth of Hungary, who claimed that drinking rosemary water led to her longevity as she lived beyond 70 years old while suffering from both gout and rheumatic disorder. Additional historic uses of the herb include its burning to purify the air near ill people to ward off infection during the plague, and it was also used by the French to kill germs during World War II (by utilising its aromatic/essential oil properties).

Rosemary is known to contain several chemicals that promote good health in human beings. The two primary active ingredients found in the herb are carnosic acid and rosmarinic acid. Carnosic acid is a preservative and antioxidant found in both rosemary and common sage. The compound has demonstrated its ability to prevent damage to skin cells by UV-A radiation and is accepted as a very powerful antioxidant. Studies have also shown that carnosic acid offers protection against harmful carcinogens. Rosmarinic acid is found in a variety of herbs other than rosemary, these include thyme, oregano, and peppermint. The compound exhibits properties as an antioxidant, anti-inflammatory, antiviral, and antibacterial.

The rosemary herb is used in modern times to treat a variety of symptoms and illnesses. The most prominent modern use of rosemary is as an antioxidant. The primary goal of the herb in this use is to prevent the damage caused by oxidative stress that occurs during many diseases. The brain is particularly susceptible to the effects of oxidative stress, as demonstrated by the condition's role in diseases such as Parkinson's disease and Alzheimer's disease. Studies have shown that the antioxidants in rosemary, such as the carnosic and rosmarinic acids, are highly effective in combating this problem.

Studies have also shown that rosemary is a potent anti-carcinogen and may play a role in treating cancer in the near future. One such study was conducted on rats and showed that rosemary, when administered in a powdered format, prevented the effects of carcinogens by 76% and decreased the incidence of tumors in mammary glands. In addition, by reducing the damage caused by ultraviolet radiation, the herb also decreases the chances of developing skin cancer.

Rosemary has been thought of as a memory booster throughout history. Recent advances in the science surrounding the herb have shown that it inhibits the breakdown of acetylcholine, which is a compound that plays a role in sections of the brain responsible for memory and reasoning. Rosemary may also promote memory function by increasing blood flow to the brain.

The herb is used by many as a natural antibacterial and antiviral. Rosemary is touted for its ability to eliminate several harmful forms of bacteria while leaving helpful bacteria undamaged. This use of the herb is particularly effective in fighting yeast infections or candida.

Since it is also commonly used as a seasoning, there are many ways to incorporate rosemary into the typical diet. The most common method is to simply season prepared food with the herb to taste. A tea can also be made by adding two teaspoons of the rosemary leaves to hot water and allowing it to steep for 10 to 15 minutes. Herb butters and oils are made by adding the leaves or oil of the plant to the butter or oil and mixing thoroughly. Rosemary is also available in capsule form.

The leaves of the rosemary herb are used to make seasoning. When making rosemary oil nearly every part of this shrubby herb is used. Oil extract from the flowers is considered to be the best in quality. The leaves are often used to make tinctures that are applied directly to the skin to treat maladies such as muscle soreness and sprained ankles.