Ambient Lighting: You can also call this general lighting.
Ambient light fills the majority of the room. It's usually produced by flush mounts, semi-flush mounts, recessed lighting or wall-mounted fixtures.
If recessed lighting is used, consider traffic flow, prevent dark spots and measure the cone of light for an adequate quantity.
Accent Lighting: Accent lighting is used to highlight a particular focal point.
Decorative pendants and chandeliers are often used for accent lighting, and dimmers are often used on these features to provide mood lighting.
Pendants can be used above a kitchen sink, island, table or dining area.
Task Lighting: This kind of light is used to better assist you in completing a particular function: like reading, cooking prep, etc.
This could be anything from desk lamps, a table lamp on a night stand, to even under cabinet lighting in a kitchen.