The word Lei is Hawaiian for garland or wreath. Most commonly a lei is made out of flowers. When you arrive at Honolulu airport you will notice the large number of people waiting to pick up their guests, all with a lei or two in hand. Giving someone a lei is a sign of affection. Plumerias and orchids are popular for use in making leis.
Have you seen the lei stands around the place in Hawaii? At the airport in Honolulu, there is an area filled with stands, dedicated to buying leis for loved ones arriving or departing the Islands. Because they are all tightly packed into this one space, they are often competing amongst each other for your sale, which is sad because the work that goes into these leis is unbelievable. I wish I could afford to buy one from each lei stand! You can barter with them on price, but show some aloha and pay the asking price plus tip - they do a great job! You will also find a number of lei stands in Waikiki, and many of the hotels have people making leis for sale in the lobby. If you are travelling internationally, check your custom inspection laws, as many countries (such as Australia) are very strict and will not let you bring flowers or plants back into the country.
Hawaiians love leis so much that they celebrate Lei Day on May 1 and 2. Not a national holiday but still noteworthy!
So what should you do with your leis if you can't take them home? My suggestion: Head to Waikiki Beach and drape them over the statue of Duke Paoa Kahinu Mokoe Hulikohola Kahanamoku - the man who made surfing one of the most popular sports around - see picture for statue!