The difference in surnames between Spain and Greece stems from family traditions and distinct laws.

In Spain

Most people have two surnames:

the father's first surname
the mother's first surname

Example:

Father: Juan García López
Mother: Ana Martínez Ruiz
Son: Carlos García Martínez

Previously, the father's surname almost always came first, but today parents can choose the order.

Furthermore:

Surnames generally do not change upon marriage;

each generation retains elements from both sides

In Spain and Portugal, the minimum age to buy or consume any type of alcohol is 18, following the removal of old exceptions for wine and beer.
In contrast, Cyprus allows legal consumption starting at 17, while Greece sets the purchase age at 18 but does not explicitly prohibit consumption in private settings.

1. Who makes the laws? (Regional vs. Central)
In Spain: Laws are not the same everywhere. Since Spain is divided into Autonomous Communities (like Catalonia, Madrid, or Andalusia), they can create their own laws regarding housing, health, or taxes. Power is shared.
In Greece: The law is the same for the entire country. Everything is decided by the Parliament in Athens. It doesn't matter if you are in Crete or Thessaloniki; the rules do not change.

The most striking legal difference is how each country treats property rights tied to history.
Spain (Absolute Ownership): If you buy a house and register it, it is 100% yours. The law protects the current buyer. There are no "hidden" owners from past wars who can reclaim it.
Cyprus (The "Guardian" Law): Due to the 1974 conflict, thousands of homes in the South officially belong to Turkish Cypriots who fled.

In Portugal: There is the "Cartão de Cidadão" (Citizen Card), which combines the ID card, health card, Social Security number, and tax ID (NIF) into a single card. All-in-one.

In Spain: Every person is an organ donor unless they have explicitly stated otherwise during their lifetime. Spain is a world leader in this system, which greatly facilitates transplants.

In Greece (Explicit Consent): The system is more restrictive. To be a donor, you generally must have registered as such or, failing that, the family must give explicit and unequivocal consent after death. This results in donation rates in Greece being historically lower than in Spain.

In Spain: Compulsory military service was suspended in 2001. Since then, the army is entirely professional and participation is voluntary.

In Greece: Military service is compulsory for all men from the age of 19. It generally lasts between 9 and 12 months. Failure to comply with this obligation can result in severe fines, a ban on leaving the country, and even prison sentences. It is a fundamental pillar of their national defense strategy.

In Portugal: It is forbidden by law to sell very thin plastic bags for fruit or vegetables. You must bring your own reusable mesh bags or use paper bags.

In Portugal, small amounts of drugs for personal use are decriminalized. A person usually does not go to prison for it.

In Spain, the rules are stricter in public places, and police can give fines more easily.

Many people think Portugal’s law is very surprising because the country treats drug use more like a health problem than a crime.

Pedro Martin Jiménez