Picked at random from a DVD player instruction manual that I had the bad fortune to be asked to translate once:

Change watch angle
While playing DVD press angle key screen show instruct title. DVD disc will change watch angle by pressing this key each time

Lock key (HOLD)
Turn according to the arrow in the button to hold all key in line controller no use, reverse is unlock to resume line controller function

Safety
The beam of unit is baneful. Do not disassemble unit, all correction must be processed by personnel
Pull out adaptor to switch off power supply while liquid dropped into unit

Long time no use unit please unload adaptor and rechargeable battery

Donot place unit under below position:
1) Place is shined by sun directly or heater around. Do not place unit on car panel or package shelf in airproof car to avoid unit malfunction
2) Dust, moist or high temperature place
3) Quaveringly place like car panel or shelf

And plenty of other "goodies" in the same manual, too..