Event Horizon
Event Horizon is the boundary of Black Hole. More scientifically to define Event Horizon is the boundary surrounding Black Hole where the influence of Black Hole is active.
Influence of Black Hole
Influence of black hole is action of black hole toward any object such as matter and energy whatever. Destructive properties of Black hole is engulf something, matter or energy whatever come under the influence of Black Hole.
Black Hole can define as a region in universe from where nothing can escape, if it be matter or energy, everything is engulfed by Black Hole.
Properties of Event Horizon
Stephen Hawking, says Black Hole is not quite black, rather it emit radiation from its Event Horizon. Black Hole radiates energy through Event Horizon. These radiation is termed as Hawking radiation.