Any communication issue or impediment that disrupts normal speech may fall under the general category of speech disorders. Such issues include stuttering and lisps, which may range from mild to severe. Those who are unable to speak at all as a result of a speech disorder are considered mute. Speech disorders differ from language disorders, which indicate an inability to understand or use words—not simply produce the sounds necessary for speech communication. While it might seem easy to identify patterns of disrupted or impaired speech, it is actually quite difficult. In fact, some estimates suggest that only about 5% to 10% of the population demonstrate a completely normal manner of speaking. Those affected by speech disorders may have difficulty producing certain sounds (usually specific consonants such as “s” or “r”), may rearrange sounds in a word, or may struggle with proper tone, intensity, sound timing, rhythm, or cadence. Frequently, the cause of a patient’s speech disorder is unknown. Some common known causes are hearing loss, neurological conditions, brain injuries, intellectual disabilities, drug abuse, physical deformities, or child abuse. Treatment often involves speech therapy. Other treatments may include correction of underlying conditions and psychotherapy. For children who suffer from speech disorders, many school districts provide speech therapy during school hours.