Soluble groups, also known as solvable groups, are a concept in algebra related to the structure of groups and their composition series. The terms "soluble" and "solvable" may reflect regional language differences, with "solvable" being more common in American English and "soluble" in British English. The discussion references Galois' results, indicating that a polynomial equation is solvable by radicals if the corresponding symmetric group is solvable, particularly for degrees less than five. Historical usage of the terms is noted, with "soluble" appearing in the 1902 Encyclopedia Britannica and "solvable" in E. Netto's work from 1892. Understanding these terms is essential for grasping the foundational concepts in group theory within algebra.