Speech is the sounds that come out of our mouths and take shape in the form of words. Many things have to happen for us to speak:
 

• The person must have a thought or idea, want or need that must be communicated to another person.
• The idea must be sent to the mouth with instructions on which words to say and which sounds make up those words.
• The brain must send signals to the muscles that produce speech - the tongue, lips and jaw.
• The lungs must have enough air to force the vocal chords to vibrate.
• The body parts must be co-ordinated and strong enough to create the right sounds and words.
• The sounds must be clear enough to form words that other people can understand.
• There must be another person to receive the communication and respond.

Many things can interfere with the development of speech. A child who has a difficulty making sounds or words may have a speech disorder.