In Greece, most people, like to enjoy themselves by listening to music or dancing, as they feel that music and dancing is one way for them to express themselves. There is one of the most popular music and dance there which is known as Rebetiko, in Greek: ρεμπέτικο, pronounced [reˈbetiko]. This name came from the word "Rebet" of South Serbian Rebetiko and referred to an undisciplined person or in Greek it is usually called as rebelos. Rebetiko itselves is a Greek urban laika songs or some urban Greek folk music that started in the late 19th century in the harbors area where the Greek labor class used to live, and it began to spread out and developed in the 20th century. In addition, this rebetiko music is very unique because it is formed by variety range of musical styles such as Greek folk music and "Island music", Byzantine, Balkan, Turkish and eastern music, the music that was played by the Greeks who were in Smyrna until 1922, the music that is used to dance by the Zeybeks, and music that was being played in Greece up to the 1920s.. However, when rebetiko is still developing, the Greek society unconciously were influenced by the political power and Rebetiko is officially prohobited in 1936, and as for the Rebetika, they were banned in 1935, because it is considered as "Greek Origin". But even this music was banned at that time, there's still some people who still play the music in the cafe, or within a small group until they were completely stopped during the German colony in Greece and the civil war.
The second type of music which is popular in Greece is called Laika (Laïkó), in Greek: λαϊκό τραγούδι, pronounced [laiˈko traˈɣuði], which means "song of the people"; "popular song". Laiko is a music genre that are composed in Greek language that match the tradition of Greek people, and it is the simplified evolution of the rebetika songs, which are easier to hear and nicer than the rebetika song. During the 60s and 70s, Laika become more important as before because laika song has eliminated the barriers of the working class music and many nightclubs or live stages usually play laika song that sung by known or new singer that will become the symbol of this fashionable nightlife in Greece. However, nowadays there are two types of Laika; the classic Laika and the contemporary laika. In the 1960s and 1970s, Laika was popular along with the singer who dominated the genre; her name is Stelios Kazantzidis. On the other hand, contemporary laika is actually talking about the modernize version of laika music. This version is actually have lots of differnece with the classic laika, as it is more cheerful, it was often used in musical, and many artists have combined the tradition of laika and entekhno to become something that make this laika version become popular. However, as for modern laika, this type of music has been mixed with modern Western influences, such as pop music and dance, which is why modern laika music often used in nightclubs in Greece.
Then, the other one is called Entekhno or "art song" as its meaning. Entekhno music arose in late 1950. This music type is the combination of orchestral music with Greek folk elements that the lyrics are based on the work of famous Greek poets. The difference of this music genre and other Greek urban folk music is that entekhno concerts usually take place outside a hall or night club in open air, and the people who are the popular entekhno music composers is called Mikis Theodorakis and Manos Hadjidakis. These people have a classical music background, and they also have combined some values of classical music to become Western art music. And in the late 1970s and 1980s, entekhno music now is getting closer to the Western classical music, and it makes this music genre becoming more well-known in the society. To sum up, these are the three popular music genre that came from Greece and there's actually still have many more other music genre that is as good as this three, but I only post Rebetiko, Laika, and Entekhno as this are the music genre that most people know and becoming one of Greece music culture.