A strongly typed language is a programming language that enforces strict rules about how data types are used. In these languages, each variable is associated with a specific data type, such as integer, string, or boolean. This means that operations on variables must be compatible with their data types, helping to prevent errors and bugs in the code. In a strongly typed language, attempting to perform an operation that mixes incompatible types, like adding a string to an integer, will result in a compile-time or runtime error. This feature promotes better code quality and makes it easier for developers to understand and maintain their programs.