What is stroke speech therapy exactly?

A type of treatment: Stroke usually impairs functions of the pharynx and laryinx (voice box) as well as soft palate and tongue in that it pertains to swallowing and speech. Speech therapy's call is to help a stroke patient to recover some of the above functions. A licensed speech therapist will work with such a patient by teaching him to use his tongue and throat muscles to be able to swallow safely and regain speech.

Relearning speech: Actually speech therapy is much more than simply relearning talking. But mainly it deals with articulation (making speech sounds), loudness, word retrieval, syntax, ability to comprehend spoken language, reading. But also includes memory training, organizational skills and more. Very valuable for many things things besides aphasia (loss of speech).