What is a "herb"?
The term itself comes from the Latin, "herba," meaning green crops. It originally referred to virtually all plants, cultivated and wild, and especially to their green and succulent parts. Today, the term has two distinct meanings. To the botanist, an herb is a non-woody plant that dies back to the ground in winter, hence "herbaceous." Herb is also used widely to mean any plant, or part derived from it, that has or once had useful properties beyond garden ornament.

At the National Herb Garden at the U.S. National Arboretum, for instance, herb is defined broadly to mean just about any plant except vegetables, grains for food or forage, or plants used only to beautify the garden. This publication deals with "herbs" in the second sense, as plants used for flavoring foods and beverages, for medicines, cosmetics, dyes, and perfumes, and for other household and economic uses. These "useful" plants include many types of vegetation, including the herbaceous, flowering plants that come especially to mind when we think of herbs (such as parsley, basil, or thyme), as well as non-herbaceous trees and shrubs, vines, ferns, mosses, and other plant groups.

The useful herbs include plants whose life cycles are annual (such as anise and basil), biennial (parsley, angelica, and clary sage), and perennial, including bay, lavender, lemon balm, thyme, yarrow, and many others. Specific herbs may be valued for their leaves (such as basil, bay, thyme), flowers (chamomile), seeds (dill, fennel), stems (angelica, chives), or underground parts (garlic, chicory). The notion of herbs as flavoring agents generally excludes those plants commonly known as vegetables, which are foods in and of themselves; that is, vegetables provide the substance, and herbs the seasoning.

A related (and also imprecise) group of economic flora consists of the spice plants. These are generally understood to be plants, usually native to the tropics, that bear aromatic fruits, seeds, or woody barks, and that are used, although not solely, to season foods. (Cooking spices may also have medicinal, aromatic, or pesticidal properties.) Examples of culinary spices include cinnamon (consisting of the bark of a small evergreen tree native to Sri Lanka), black pepper (the unripe berries of a native Indonesian plant), and cloves (the dried flower buds of an evergreen tree from the Moluccas, known historically as the "Spice Islands.")

There is often confusion over which plants are herbs and which are spices. One example of the inconsistency in these designations occurs with Coriandrum sativum, a plant native to southern Europe, the Mediterranean region, and northern Africa, which yields both an "herb" and "spice." Its green leafy parts, known as cilantro, are generally considered an herb; while its aromatic seeds are typically deemed a spice.

Herbs and spices have been used for many thousands of years. They provide a tangible link to ages past, when innumerable kinds of plants were an integral, daily part of home and community life. In Western societies prior to this century, people once turned to herbs to fulfill their physical and spiritual needs: to cure illness, season foods, and dye cloth; for their cosmetic properties and pleasing or repellent aromas; as well as for their magical or symbolic qualities.

Although interest in particular herbs has waxed and waned over time and across cul-tures, we have witnessed a general decline in herbal popularity in the industrial era. Botanicals and other natural products have been eclipsed by purified or wholly synthetic drugs, food additives, chemical dyes and pesticides, and other manufactured products. This trend has been partially reversed in the late 20th Century, however, as shown by expanding herbal interest and activity from many quarters. This renewed focus consists, in part, of rediscovery and reevaluation of our pre- industrial herbal heritage, along with new interest in beneficial plants as renewable, biodegradable, or less-toxic resources, and greater interest in the cultural traditions of other groups.

Plant-derived medicines have long contributed to human health and well-being, and today, plant materials are present in, or have provided the models for, a significant proportion of Western drugs. A number of commercially-proven drugs used in modern medicine were initially used in crude form in traditional or folk healing practices, or for other purposes that suggested potentially useful biological activity. Some examples include the muscle relaxant, curare; pain-killer, morphine; antimalarial, quinine; and heart- regulator, digitalis. For our smaller living spaces, many herbs are suited to indoor culture and container gardens. Beyond the home garden, market gardeners and small farmers seeking diversification are finding that herbs may be a profitable alternative to conventional cash crops. Rekindled interest in their natural pest-deterrent properties may also mean an expanded role for the plants traditionally considered "herbs" in commercial agricultural production.

Herbalism
Herbalism, also known as herbal medicine, herbology, and phytotherapy, is a folk and traditional medicinal practice based on the use of plants and plant extracts. Utilizing the healing properties of plants is an ancient practice. People in all continents have long used hundreds, if not thousands, of indigenous plants for treatment of various ailments dating back to prehistory. These plants are still widely used in ethnomedicine around the world.

The use of and search for drugs and dietary supplements derived from plants have accelerated in recent years. Pharmacologists, microbiologists, botanists, and natural-products chemists are combing the Earth for phytochemicals and leads that could be developed for treatment of various diseases. In fact, many modern drugs have been derived from plants.

Herbs have been used since the dawn of time as medicines and, in fact, many common drugs are ,in actual fact, made from herbal extracts. The natural chemical properties of certain herbs have been shown to contain of themselves, medicinal value. However, unlike conventional medicine, herbalists use the 'whole' herb or plant rather than isolating and breaking down chemical compounds and then synthesising it. This is because the plant, being a part of Nature, is said to represent perfect balance; healing requires the natural combination of elements in the plant or herb, not just a single chemical within it.