A gift or a present is an item given to someone without the expectation of payment or anything in return. An item is not a gift if that item is already owned by the one to whom it is given. Although gift-giving might involve an expectation of reciprocity, a gift is meant to be free. In many countries, the act of mutually exchanging money, goods, etc. may sustain social relations and contribute to social cohesion. Economists have elaborated the economics of gift-giving into the notion of a gift economy. By extension the term gift can refer to any item or act of service that makes the other happier or less sad, especially as a favor, including forgiveness and kindness. Gifts are also first and foremost presented on occasions such as birthdays and holidays. In many cultures gifts are traditionally packaged in some way. For example, in Western cultures, gifts are often wrapped in wrapping paper and accompanied by a gift note which may note the occasion, the recipient's name and the giver's name. In Chinese culture, red wrapping connotes luck. Although inexpensive gifts are common among colleagues, associates and acquaintances, expensive or amorous gifts are considered more appropriate among close friends, romantic interests or relatives. Gift-giving occasions may be: An expression of love or friendship An expression of gratitude for a gift received. An expression of piety, in the form of charity. An expression of solidarity, in the form of mutual aid. To share wealth. To offset misfortune. Offering travel souvenirs. Custom, on occasions (often celebrations) such as A birthday (the person who has his or her birthday gives cake, etc. and/or receives gifts). A potlatch, in societies where status is associated with gift-giving rather than acquisition. Christmas (throughout the history of Christmas gift giving, people have given one another gifts, often pretending they are left by Santa Claus, the Christ Child or Saint Nicholas). Feast of Saint Nicholas (people give each other gifts, often supposedly receiving them from Saint Nicholas).