Mold, Mildew, Algae or Moss

Can anyone provide me with an easy way to be able to identify what the difference is between Mold, Mildew, Algae and Moss on the exterior of vinyl siding? If not, how would you report something like this? See pic below.

Please advise,


Mildew is a misnomer. Mildew is mold is fungi.

Just call it organic growth and tell them to buy a pressure washer.

What Joe said.
They’re all a sign of high moisture levels and the condition may return unless something changes.

I was told by a siding guy not to use high pressure on siding only use siding cleaner and low pressure . Problem people stand on the ground spray up, causing water to be forced under the siding . and moisture to be trapped in some places. AH you say there is drip holes yes there is but siding does not alawys lay level. Guess what he was right i used a pressure washer on my home a few years ago , did a great job when i added on to my home we took the siding off to find Moisture damage in lines .
Where i did not have to wash the siding nothing . Also the siding cleaner works great too, use wash every year now maybe every 2 .

All great responses. I think I have a good idea how to word this now. Thanks everyone.