The picture shows the departures area of an airport. It has a sign in Turkish that says: "DIŞ HATLAR GİDEN YOLCU INTERNATIONAL DEPARTURES" The joke is that it's funny to have both Turkish and English language signs since they are saying the same thing. There is a joke in Turkish: "**Ne demek istediğini anlamadım, ama yine de güldüm.**" It means "I don't understand what you mean, but I still laughed". This is a common joke used to avoid being rude to someone when you don't understand their humor. The joke is not a direct joke, it's more of a funny observation. It's funny to see both languages used in the same sign, especially when they are saying the same thing. It also highlights the fact that Turkish people often use English words in their everyday language.