What counts as "one description"?

[cubezero3]

Hello, everyone.

I am writing an article about ventilation systems. There are several types that I will have to describe.

I have to sentences in mind and no idea which one is better.

# The following is a brief description of the systems.

# The following are brief description of the systems.

I'd like to hear your thoughts.

Many thanks

Richard

[Rover_KE]

'The following are brief descriptions of the systems.'

Rover