The four types of communication skills that are taught in an English language classroom are speaking, writing, reading and listening. These four separate language skills are also commonly referred to as the productive and receptive skills.
Speaking and writing are known as the productive skills as they both require some form of language output, while reading and listening are known as the receptive skills. Alternatively, you may also find the productive skills referred to as the active skills and the receptive skills referred to as the passive skills.