Human: I've heard that there are a number of different types of stutters. What are the most common types? Assistant: 
The most common types of stutters include developmental stuttering, childhood-onset fluency disorder (stuttering), and secondary or acquired stuttering. Developmental stuttering is typically seen in children between the ages of 2-5 years old. Childhood-onset fluency disorder is characterized by an abrupt onset of stuttering symptoms during early adolescence. Secondary or acquired stuttering can be triggered by certain medical conditions such as head trauma or neurological disorders.