Kids' plastic blocks are a popular toy that has been around since 1949. The most well-known brand of these blocks is LEGO, which is a Danish company that produces interlocking plastic blocks that can be used to create various structures and models. LEGO blocks come in a variety of shapes, sizes, and colors, and can be used to build anything from castles to robots. They are a great way to encourage creativity and problem-solving skills in children.