Comparing "shangliang" and "taolun"

While 商量 and 讨论 both are verbs and can be translated to mean “to discuss”, usually these two words cannot be used interchangeably. 商量 is for the purpose of solving problems, whereas 讨论 is used to exchange ideas and opinions. Another difference is that 商量 is used in informal situations, whereas 讨论 is more often used in formal situations.