The ancient Maya civilization developed a fully written hieroglyphic script and advanced mathematical and astronomical systems. They inhabited an area that encompassed southeastern Mexico, Guatemala, Belize, western Honduras and El Salvador. The Maya civilization consisted of northern lowlands, highlands, and southern lowlands. Their society had distinct social levels including royalty, nobility, and slaves. They built structures from local resources, ranging from thatch-roofed huts for most to larger buildings for rulers and priests, and constructed pyramidal temples central to their nature-based religion.