Awareness ribbons are used to symbolize various concerns, right from diseases, like bone cancer (symbolized by a white ribbon) and HIV AIDS (symbolized by a red ribbon) to issues pertaining to the society, such as environmental protection (symbolized by a green ribbon) and sex trafficking (symbolized by a blue ribbon). The color of these ribbons plays a crucial role in depicting the cause. The use of such ribbons to spread awareness can be traced back to the 1970s, when the wives of the American soldiers held hostage in Iran used yellow ribbons as a part of the awareness program. The idea became so popular within a short span of time, that when these soldiers returned home in 1981, they were welcomed with hordes of such yellow ribbons. Awareness Ribbon Colors and Meanings At times, a single color is used to represent many awareness campaigns, and at times, a single concept or issue will have several attributes, each of which will be represented by a different color. The color of cancer awareness ribbons, for instance, differs from one type of cancer to another. While white ribbon is used to symbolize bone cancer, blue is used for colon cancer, gray for brain cancer, and pink for breast cancer. Given below are the various other colors of ribbons and their meanings. Yellow Ribbon: It was the yellow ribbon that marked the beginning of the use of colored ribbons to spread awareness. Other than its use to symbolize the deployed troops, the yellow ribbon is used for suicide awareness and prevention program. It is also used as a symbol for the 'help unlock the second prison' program, which assists the ex-convicts. In the health sector, it is used in sarcoma and bone cancer as well as endometriosis awareness programs. White Ribbon: It is used to spread awareness about various health issues, including bone cancer and multiple hereditary exostesis, as well as issues pertaining to the society, such as gender violence and the gay-teen suicide. Blue Ribbon: Though the color blue is most often associated with colon cancer, different shades of blue are used in various other awareness programs. While sky blue ribbon is used for prostate cancer awareness, navy blue ribbon is used to spread awareness about sex trafficking and slavery. In general, blue ribbon is used in Bring Home Our Troops campaign, child abuse awareness, tuberous sclerosis awareness, anti-tobacco and anti-second hand smoke awareness (Canada), and the International No Diet Day. Red Ribbon: Red ribbons are used in AIDS awareness and vasculitis awareness as far as the health sector is concerned, and for substance abuse awareness as far as issues related to the society are concerned. Red and Blue Ribbon: It is being used as the ribbon for the Haiti Recovery and Restoration awareness following the devastating 2010 Haiti earthquake. Green Ribbon: Green ribbons are used in a range of awareness programs, including the organ transplantation and donation awareness, aging research awareness, kidney cancer awareness, and environmental protection awareness. In 2009, it was used as a symbol for election protests in Iran. Pink Ribbon: One of the most widely acclaimed color as far as awareness ribbons are concerned, pink is used to spread awareness about breast cancer. Gold Ribbon: A gold ribbon is used as a symbol for leukemia and child cancer awareness programs. Blue and Pink Ribbon: A ribbon of this color combination is used in infertility awareness, infant loss awareness, and pregnancy loss awareness programs. It is also used in inflammatory breast cancer awareness and as a symbol of genital integrity. Jade Ribbon: A jade ribbon is used to spread awareness about hepatitis B and liver cancer. Periwinkle Ribbon: This ribbon is used to spread awareness about pulmonary hypertension, eating disorders, and stomach cancer. (The color is derived from the color of periwinkle―a poisonous plant with blue colored flowers.) Violet Ribbon: A violet ribbon is used as a symbol for a Hodgkin's lymphoma―a type of cancer involving white blood cells. Silver Ribbon: The silver ribbon is used to spread awareness about the brain disorder and disability. In Australia, it is also used to spread awareness about ovarian cancer. Purple Ribbon: A purple ribbon is used to spread awareness about a range of disorders, including chiari malformation, cystic fibrosis, fibromyalgia, Alzheimer's disease, pancreatic cancer, etc. Other than these, the purple ribbon is also used to spread awareness about domestic violence, and to symbolize religious tolerance and the Workers' Memorial Day. Orange Ribbon: The orange ribbon is also used to spread awareness about various illnesses, such as leukemia and lymphoma, multiple sclerosis, ADHD, etc. It is also the symbol of animal protection awareness and kidney cancer survivorship and awareness. In Australia, it signifies anti-racism, and in Nigeria, it is a symbol for energy awareness. Gray Ribbon: The gray ribbon is used to spread awareness about diabetes, brain cancer, and asthma. Black Ribbon: Famed for the Anarchist Black Ribbon Campaign, the black ribbon is also used to spread awareness about melanoma and narcolepsy. In the United States, it is used in mourning and remembrance of the Virginia Tech massacre. Other than these awareness ribbons, there also exist some multicolored ribbons which symbolize a cause/campaign. For instance, the multicolored ribbon depicting several puzzle pieces is used in autism awareness. Similarly, the Ribbon of Saint George, with black and orange bi-color pattern, is used to commemorate World War II in the post-Soviet countries. Wearing these colored ribbons is one of the most novel ways of spreading awareness about different campaigns, and its successful implementation in various fields speaks a lot in this regard.