Essential oils are concentrated oils derived from plants. Here’s how Retha, a certified aromatherapist from Plant Therapy, defines an essential oil, “An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are generally extracted by distillation, often by using steam.” Essential oils are used for their aromatherapy benefits (air freshener and homemade candles) and also for their beneficial cleaning properties (i.e. used in all-purpose surface spray and stain remover). New to essential oils for cleaning? Start with this essential oils podcast episode and this essential oils 101 cleaning guide.