What is a Speech and Language Impairment?

From the Minnesota Department of Education: The Individuals with Disabilities Education Act (IDEA) defines speech/language impairment as…
a communication disorder such as stuttering, impaired articulation, language impairment or a voice impairment that adversely affects a student’s educational performance.

• Fluency disorder means the intrusion or repetition of sounds, syllables, and words; prolongation of sounds; avoidance of words; silent blocks; or inappropriate inhalation, exhalation, or phonation patterns. These patterns may also be accompanied by facial and body movements associated with the effort to speak.
• Voice disorder means the absence of voice or presence of abnormal quality, pitch, resonance, loudness, or duration.
• Articulation disorder means the absence of or incorrect production of speech sounds or phonological processes that are developmentally appropriate (e.g. lisp, difficulty articulating certain sounds, such as l or r). 
• Language disorder means a breakdown in communication as characterized by problems in expressing needs, ideas, or information that may be accompanied by problems in understanding.