My best answer would have to be:

Wealthy Affiliate is a service that provides you with everything necessary to start your own niche website and make money from it.

There is a LOT more to WA than only that, but that explanation gives you a basic understanding.

The image below explains in more detail exactly what is offered for Free and Premium members:

As you can see, Wealthy Affiliate provides you with a lot.

Free members are limited as to what they have access to and Premium members have access to every single thing offered by WA.

One of the greatest aspects of WA is Free and Premium members can have success at WA. 

https://my.wealthyaffiliate.com/training/what-is-wealthy-affiliate-how-to-get-started/a_aid/fd156b29