Both! In Brazil there are two ways of greeting people. If you are in a relaxed enviroment and you just met someone, you can wither shake hands or give two beijinhos (the quantity will depend on which state you are). There’s an etiquette that says that only women can stand the hand to the male, and if she doesn’t means he’s not allowed to touch her. Although this rule still applies, we can still use the cheek to cheek kiss.
Please have in mind that we don’t really kiss the other person’s face with our mouths. We touch cheek to cheek and blow the kisses in the air. We always go to our left side first, that is, we take our right cheek to the other person’s right cheek. Normally that kiss is accompanied with one of your arms around the person waist. Like a small side hug.
In São Paulo they only give one kiss.
In Minas Gerais, we give three kisses alternating cheeks. And single people often say that the third kiss is to help find marriage. We say: “3 pra casar”. (More religious state) Those will be used even within your family. Not only with people you’ve just met. Like cousins, uncles, grandma, grandpa, etc…
Please notice that man do not kiss man; they shake hands. The kisses are between two women or a man and a woman.
At work, you usually shake hands when you first meet someone no matter what gender the other person is.
Brazil to the World 