Buenos días (Good day) - Used in the morning from sunrise until around noon.
Buenas tardes (Good afternoon) - Used from around noon until sunset.
Buenas noches (Good night) - Used from sunset until sunrise.
When meeting someone for the first time, it is customary to shake hands and make eye contact. If you are close friends or family members, you may also kiss each other on the cheek or give a hug.
It is important to note that these greetings may vary depending on the region of Spain you are in. For example, in the Basque Country, the traditional greeting is "Egun on" (Good day) or "Egun beroi" (Good hot day). In Catalonia, the traditional greeting is "Bon dia" (Good day) or "Bona tarda" (Good afternoon).