The Maya were a Mesoamerican civilization. They had the most advanced writing system in the Americas prior to European contact. They used sophisticated mathematic systems and had complex and useful cyclical calendars. Spectacular art and monumental architecture were two other notable accomplishments of this civilization.
What country did they live in? 
The ancient Mayans lived in what is now known as southern Mexico and northern Central America including Guatemala, Belize, Honduras, Yucatán Peninsula and El Salvador. Their descendants still live there today, and many of them speak the Mayan languages.
What did their buildings look like? 
The Mayans were master architects, building pyramids and even entire cities, many of which are still standing today.
Mayan pyramids were made of stone. The stone was carved to create a stair-step design. On the top of each pyramid was a shrine dedicated to a particular deity. Rituals thought to influence the Gods were held in these shrines.
Mayan cities grew around the pyramids. They consisted of plazas connected together by sacbeob (whiteway) causeways. There appears to have been little planning in their design; the topography of the region influenced the type of buildings constructed. For example, cities in the hills had tall towers, while cities built on limestone grew into large municipalities.
The largest plazas were at the heart of Mayan cities. They contained governmental and religious buildings, such as the royal acropolis, great pyramid temples, and occasionally ball-courts. Temples and observatories were always constructed so they followed the Mayan interpretation of the orbits of the stars. Outside of this center were less important temples and shrines. At the outskirts lay the homes of the common people.
Building Materials 
The Mayans lacked many tools, such as metal tools, pulleys, and perhaps even the wheel. They did, however, have an abundance of materials. The most common material was limestone, taken from local quarries. Limestone was easy to work, and only hardened once removed from its bed. In addition, it could also be used as mortar or stucco. Common homes used wooden poles, adobe (a mixture of straw and sandy clay), and thatch; however, houses made of limestone have been found as well. In the city of Comalcalco, fired-clay bricks have been found as a substitute for stone. The Mayan's used clay, stone, limestone, thatched hay, wooden poles, and metal to make common day houses.
What did they eat? 
The Mayans grew a wide variety of crops, including corn (maize), Amaranth, manioc, and sunflower seeds. These crops were grown in permanent raised fields, terraces, forest gardens, and managed fallows. There was also harvesting of wild crops. The Mayans ground cacao and mixed it with water to make the first chocolate.
What did they wear? 
When the king appeared in public, he wore white robes and a gold crown on top of his head, decorated with Quetzal (a type of bird) plumes.
During wartime, the Mayans wore masks, while commanders wore robes made of silver and gold. Some Mayan clothes were made of deer skin. Usually women made the clothes.
What did their writing look like? 
The Mayans wrote using a series of glyphs (symbolic pictures), which were painted on ceramics, walls, or bark-paper codices (books), carved in wood or stone, or molded in stucco. Each glyph represented a word. Mayans wrote numbers vertically.
The Mayan script was used up until the arrival of the Spanish. Although many Mayan centers went into decline (or were completely abandoned) during or after this period, many Mayans still had the skill and knowledge of Mayan writing, and the early Spanish conquistadors knew of people who could still read and write the script. Unfortunately, the Spanish however believed that the Mayan books were evil so by the end of the 16th century, almost all knowledge of the Mayan script was lost.
Attempts to decipher the Mayan script came in the 19th century. Investigators were soon able to decipher the Mayan numbers and portions of texts related to astronomy and the Mayan calender. Most of the Mayan script has since been deciphered, but work still continues today. The Mayan calendar ends at the year of 2012, when they believed the world would end.
What did they believe? 
The Mayans believed that time was cyclical, that is, it goes in circles. The Mayan shaman interpreted these cycles by looking at the number relations of all their calendars. If the interpretations of the shaman showed bad times ahead, human sacrifices would be performed to make the gods happy. They left behind a prophesy that the world would end on December 21, 2012 and bring about the fifth cycle of the world.
According to Mayan mythology, there were thirteen heavens and nine underworlds, with one god for each. Natural elements, stars and planets, numbers, crops, days of the calendar and periods of time all had their own gods.
The creation story of the Mayans is found in the Popol Vuh ("Council Book" or "Book of the Community"). According to the book, the gods Tepee and Tucuman's decided that, in order to preserve their legacy, they had to make a race of beings who could worship them. Earth, along with the animals, was created. Man was first made out of mud but then he fell apart. Other gods were summoned and man was next created of wood but had no soul. Finally, man was made out of maize by even more gods.
The Mayans worshiped Gods and Goddesses and they believed to make the Gods and Goddesses happy they had to make human sacrifices.
What is left of them today? 
The ancient Mayans abandoned their large cities suddenly. To this day, no one is still certain why. However, the Mayan people never died out; their descendants still live in Mexico and Central America. The Mayan's legends and royal lineage is written in a book called Popul Vuh. The word 'hurricane' comes from the name of a fearsome Mayan god named Hurakan who is mentioned in this book.
Mayans painted their bodies red, black, white, and blue and thought crossed eyes were cool. They tied objects to their babies' heads to give them crossed eyes. They tied boards to their babies' heads to flatten them too.
At the start of the 21st century, there were about 6 million Mayans living in the Mexican states of Yucatán, Campeche, Quintana Roo, Tabasco, and Chiapas, and in the Central American countries of Belize, Guatemala, and the western portions of Honduras and El Salvador.
The largest group of modern Mayans is found in the Yucatán region of Mexico. They speak both "Yucatec Maya" and Spanish, and are generally integrated into Mexican culture. More traditional Mayans are found in Guatemala. Many of them wear traditional clothes and practice traditional customs. The most traditional Mayans are a group called the Lacandon, who avoided contact with outsiders until the late 20th century by living in small groups in the rain forests.
There are many Mayan buildings that were once part of cities still standing today. The most important ones are: Chichen Itza, Coba, Copán Kalakmul, Tikal, and Uxmal. These cites lay forgotten for centuries, until modern-day explorers rediscovered them. Archaeological surveys and excavations were conducted (and are still being conducted) on some of these sites, revealing more about Mayan culture. Today, some cities can be visited by tourists.
Are some of them famous even today? 
There are indigenous people in Southern Mexico, Guatemala, and Honduras who are descended from the Maya. One of the most famous of them is Rigoberta Menchu, a Quichè Indian. She wrote about the struggles of her people in her book I, Rigoberta Menchu. She received a Nobel Peace Prize.