The Family Phalangiidae is a group of arachnids commonly known as daddy longlegs or harvestmen. They are characterized by their long, slender legs and oval-shaped bodies. While the name Phalangiidae is commonly used to refer to this family of arachnids, there are other less common synonyms that may be used. These include Opiliones, which is derived from the Latin word for shepherd, and Eupnoi, which translates to "good breath." Other synonyms include Palpiornes and Laniatores. Regardless of the name used, these fascinating creatures are known for their important role in the ecosystem, serving as both predators and prey.