Stuttering, also known as stammering is a speech disorder that affects the flow and rhythm of speech. People who stutter may repeat or prolong sounds, syllables, or words, hesitate, or have difficulty starting words. Stuttering can also involve physical tension or struggle behaviors, such as eye blinking, facial grimacing, or body movements which occur while speaking. Stuttering can vary in severity and can be situational, meaning that a person may stutter more in certain situations or when speaking to certain people. Stuttering can also be accompanied by anxiety or negative feelings, such as embarrassment, frustration, or shame. The cause of stuttering is not fully understood, but it is believed to involve a combination of genetic, neurological, and environmental factors. Stuttering often begins in childhood, and early intervention with speech therapy can be helpful in managing the disorder and improving communication abilities. While there is no known cure for stuttering, many people who stutter are able to live successful and fulfilling lives with the help of therapy and support.