When we refer to "speech", we are referring to how we say and produce sounds in order to formulate words. Speech includes articulation (how we make speech sounds), voice (how we use our vocal folds and breath to make sounds), and fluency (the rhythm of our speech). 

Some students may present with an articulation disorder or a phonological disorder. 

An articulation disorder is characterized by difficulty making sounds. For example, sound errors can be a substitution, deletion, or addition. Not all sounds errors are considered a disorder. Refer to the speech sound development chart for age of acquisition.