Language is a system used to represent thoughts and ideas. Language is made up of several rules that explain what words mean, how to make new words, and how to put words together to form sentences. A community must share the same language in order to attach meaning to utterances. The method of delivery of language may be visual (e.g., American Sign Language), auditory (e.g., English), and/or written. Humans are the only creatures innately capable of using language to discuss an endless number of topics. Language disorders can be developmental or acquired (e.g., specific language impairment and aphasia, respectively).