A kiss on the cheek is a way to greet or say goodbye to a close friend or relative, or to flirt with someone. Although a kiss on the cheek usually means the physical act of kissing another person on the cheek, it also sometimes involves light cheek-to-cheek contact with another person while making a kissing noise.
Kissing another person on the cheek is just one example of how kisses are used to express emotions to others. Due to the close interaction that is required for nearly all kisses, this form of interaction is usually reserved for expressing emotions between two people who are close to one another.
The most romantic out of all the kisses is generally considered the French kiss. As such, this is a type of kiss that is usually reserved for lovers. It involves open-mouth kissing in which the tongues touch. Despite the name, the French kiss did not start in France. In fact, it is believed that this was a name that British and American soldiers used and brought back home after World War I. Although American and British soldiers were the first to give the French kiss its name, the origins of this type of kissing is still not known.