While researching on the Internet, I came across this great example of plain language writing. Notice in these two example paragraphs that the writer is explaining the same idea but to two very different audiences.
For everyday people: Common traumatic injuries of horses include fractures, cuts, puncture wounds, infections, and a muscle weakness syndrome called exertional rhabdomyolysis. These conditions require immediate veterinary care. In cases of trauma, keeping the horse calm is a primary concern. This can help prevent further injury. Emergency first aid may also be required.
For veterinarians: Common emergencies involving the musculoskeletal system include fractures, luxations, lacerations, puncture wounds, infections, and exertional rhabdomyolysis. Although many of these conditions cannot be treated in the field, accurate identification and provision of appropriate emergency treatment are essential for a successful outcome.
For everyday people: Eye injuries are usually caused by trauma. They include cuts, scratches, and penetrating injuries from foreign bodies. Direct blows to the eye can cause retinal detachment. The eyes should be protected from direct sunlight as much as possible (see Emergencies: Eye Emergencies).
For veterinarians: Ocular injuries are usually traumatic in origin, and include periocular lacerations, corneal lacerations or foreign body penetrating injuries, and direct blows to the eye causing retinal detachment. (Also see Ophthalmic Emergencies.)
Source: The Merck Manuals