The American Speech-Language-Hearing Association definition: 
A speech-language pathologist (SLP) work to prevent, assess, diagnose, and treat speech, language, social communication, cognitive-communication, and swallowing disorders in children and adults.
These disorders include: 1-Speech sounds problems: problems in the ability to say sound and put them together. 2-Language: problems in the ability to understand what we hear and read and how to use words to convey ideas and feelings. 3-Social communication (Pragmatics): following rules, taking turns, body language and gestures problems. 4-Voice: how healthy the voice is. 5-Fluency (Stuttering): pebbles with speech flow. 6-Feeding and Swallwing: include sucking, chewing, swallowing food and liquids problems.
What is speech?
Speech is the way we say sounds and words and includes: 1-Articulation which is the process of using mouth, tongue and lips to produce sounds. 2-Voice which is the result of using the vocal folds and the breath. 3-Fluency which is the rhythm of the speech.
What is Language?
Language is the words and sentences (cods) we use to share ideas and communicate. * receptive language: the ability to understand words. *expressive language: the ability to use words and sentences to convey meaning and massages to others.
What is communication?
Communication is the process of exchanging massages between two or more people using verbal or nonverbal language.
What is language disorders?
1-Receptive language disorder: having problems in understanding what other people say 2-Expressive language disorder: having problem sharing ideas and feelings with other by using verbal language. 3-In general: language disorders include: understanding, writing, reading and talking.
What is speech disorder?
People with speech disorder might experience problems with: 1-Not be able to say sounds clearly. 2-Have a raspy or a hoarse voice. 3-Stutter: repeat sounds or pause when speak.
source:ASHA.org
Awareness👩🏻⚕️وَعْي 