They are called masons according to what i studied in humanities, not quit sure if they are freemasons
Egypt
To take the kings and their belongings to heaven with them
limestone and granite were the main materials used to build pyramids. Some of the later pyramids were made from mud brick with a casing of limestone.
The main pyramids were not built with steps. There were stone caps that left it with a smooth surface, but over the centuries, people have taken them for use in other buildings.
The Ancient Egyptians constructed pyramids as tombs for their pharaohs (kings).
I believe that they are three main pyramids in Giza.
That's a difficult question to answer because it depends on your definition of pyramid. Most people think of the Egyptians as the main builders of pyramids but there are pyramid structures built by Ancient South American and Asian civilisations also. The Egyptians built them as tombs, the Aztecs built them as temples.
Aztec pyramids were typically built with a square base and four staircases leading to the top. They were aligned with the cardinal directions, with the main staircase facing east towards the rising sun. The positioning of the pyramids was significant in Aztec religious beliefs and rituals.
Religion and the exhibition of political prowess are the main reasons why the pyramids were built: most of them were temples dedicated to the Mesoamerican gods, where many types of rituals were celebrated, such as offerings and human sacrifices.
There are 138 pyramids discovered in Egypt as of 2008.
You can't tell without seeing the pyramids.
Not nearly! There are two other, similar, pyramids right next to it! As of 2008, there are a total of 138 Pyramids in Egypt, including the main three. In addition, there are a lot of Pyramids in Nubia (Numbering 220, there are more than in Egypt), although they look a bit different (They are much smaller, and taller for their size than the ones at Giza.) Although those are the two major Pyramid-building cultures, many cultures built some sorts of Pyramids. The Greeks and the Romans both built a few Pyramids. And, of course, there's the Luxor Hotel in Las Vegas :). However, there is another form of structure built in the ancient world similar to a Pyramid. These are called Ziggurats, although they are sometimes also referred to as Pyramids. The main builders of Ziggurats were the Sumerians and the Mayans, but you can find Ziggurats ANYWHERE if you look hard enough. They appear in Spain, Nigeria, Indonesia, China, India, With a sufficiently loose definition North America, and Peru.