Definitions

Speech therapy aims on receptive language, the ability to comprehend words spoken to you and expressive language, the ability to use words to express yourself. It deals with the procedures of producing words like volume, pitch, articulation and fluency. Children may need speech therapy for pursuing milestones which have been delayed. For adults, it is needful after any traumatic accident or a stroke that changes their ability to speak.

Few children may require help with language, few others have problems with speech mechanics and few may require every kind of help in speech. A speech therapist, also known as a speech language pathologist or a speech teacher will find certain activities to strengthen the child in areas of weakness. For mechanics, it might involve exercises to strengthen the lips and tongue, such as licking or whistling. For language, it may involve games to improve conversation and comprehension.

Resource: http://specialchildren.about.com/od/speechtherapy/g/SLP.htm