The most popular type of Christmas tree is the evergreen coniferous tree, typically a fir, pine, or spruce tree. These trees are known for their strong branches and dense needles, making them ideal for supporting ornaments and lights. They also have the advantage of retaining their needles and staying fresh for a longer period of time compared to other tree types. Fir trees are often preferred for their full, symmetrical shape and classic Christmas tree look, while pine trees tend to have more fragrant needles and a more rustic, outdoor feel. Spruce trees are also commonly used as Christmas trees and are known for their strong, straight branches.