Essential oil is widely used in our life, but sometimes we still don't know what is the essential oil, today we are here to discuss what is essence of life.An essential oil is a highly aromatic, concentrated oil that is distilled (most frequently by steam or water) from the leaves, needles, stems, flowers, bark, roots, or other highly aromatic plant parts. While most essential oils are water or hydro distilled, citrus essential oils are either cold pressed or steam distilled from the rinds (peels) of citrus fruits

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Essential oils are highly concentrated, and a little goes a long way. Although they are natural and most smell wonderful, it is important to learn about and respect essential oil safety. Essential oils are highly beneficial and effective when used carefully and with realistic expectations. However, improper use of essential oils can be harmful. But aromatic oils that are not specifically produced by either steam or hydro distillation or cold pressed in the case of citrus oils are not considered and should not be referred to as essential oils.

Essential oils, contrary to the use of the word "oil" are not really oily-feeling at all. Most essential oils are clear, but some oils such as blue tansy, patchouli, orange and lemongrass are amber, yellow, green or even dark blue in color.

An Introduction to the Benefits of Essential Oils
The natural chemical* composition and aroma of essential oils can provide valuable psychological and physical therapeutic benefits. These benefits are usually achieved through methods that include inhalation and topical application of the diluted essential oil to the skin.
Essential oils are comprised of naturally occurring chemicals. The composition of 100% pure Lavender Essential Oil, for example, includes Linalyl acetate and Linalol. Some individuals who are new to working with essential oils can become confused and frightened when the word chemical is used in conjunction to essential oils. Pure essential oils are not adulterated with additives of any kind. However, pure essential oils are indeed comprised of naturally occurring chemicals, also sometimes referred to as constituents.

When left undiluted or not diluted adequately, essential oils can pose a risk of sensitization or irritation when applied topically. When not properly diluted, some can also be phototoxic. Prior to topical application, essential oils are first diluted with a carrier oil such as jojoba, sweet almond oil or apricot kernel oil.
Careful inhalation can also provide therapeutic benefit as the essential oil molecules enter the lungs and are absorbed into the bloodstream. Methods of inhalation include the use of diffusers, inhalers and aromatic jewelry.
Essential Oils are usually sold for individual use in very small bottles.
Essential oils can vary greatly in quality and price. Factors that can affect the quality and price of the oil include the rarity of the botanical, the country of origin and growing/climate conditions, quality standards of the distiller, and how much oil is produced by the botanical.
Essential oils can often be purchased as blends of several essential oils. The advantage to purchasing pre-made essential oils blends is that you can save from having to buy every essential oil individually. When purchasing blends from experienced, reputable essential oil suppliers, you also have the advantage of using blends made by experienced aromatherapists and artisans. The disadvantage is that you have no personal control over the blend by not mixing it yourself nor can you reliably mix the blend with other oils as you could when formulating blends from scratch yourself.

Essential Oils are Not the Same as Perfume Oils or Fragrance Oils
Where essential oils are derived directly from natural botanicals, perfume oils and fragrance oils contain artificial substances and do not offer the therapeutic benefits that essential oils offer. See the What are Fragrance Oils? article for information about fragrance oils and why they are not used in aromatherapy.