There are seven countries in Central America, but only five of them constitute the entity that has been trying to unite into a Federation, following the political structure of the U.S.A.
Belize, once a part of Guatemala at the extreme north, and leased to the U.K., turned into a Colony and
was granted Independence not too long ago; and Panama at the extreme south, once a part of Colombia
and later home of the United States constructed and controlled Panama Canal, until President Carter decided to let it go, are excluded from the pretended Federation; that has failed to become a reality, in part due to some Nationalistic groups that resists loosing individuality, and petty arguments like "Where would the capital of the Federation be?"
Nonetheless, in spite of differences such as "slang" and accent in their speech, currency and
small variations in temperament, they have accomplished a limited union that permits Central Americans to cross borders with no other papers than their personal ID, issued by the country of birth.

Customs are similar.- As a
rule, Central Americans love to sit around with friends - and friends to be -
to socialize and consume navigable quantities of beer or liquor; rum, followed closely by vodka, mixed with Coca Cola a favorite drink and called a "Cuba Libre" except in Nicaragua where they prefer Pepsi-Cola and call it a "Nica Libre". Bourbon is practically unknown, and ordering a whiskey, will invariably produce a Scotch.
Central Americans generally get along well. Some times they tease each-other in jest, each nationality having a nick-name: a Guatemalan is a "Chapin", a Salvadorean a "Guanaco", Honduran"Catracho",
Nicaraguan "Chocho" and Costa Rican a "Tico".
Each country has its typical cuisine and special dishes, which may include some non traditional food, like iguana eggs in a special native sauce called "alguashte" (from the Mayan dialect "Nahuatl"), still spoken in some parts of El Salvador.
There are only two seasons in Central America: Rainy and Dry. They all enjoy a very good climate, Guatemala's being the best and it is known as "The Eternal Spring Country".
If you are curious and like to travel, give it a whirl. You'll have a fantastic time!