What does limited tool use for Basic and Standard licenses mean?

[Emilbrundage]

Many tools, like Union​, state that the Basic and Standard licenses provide "Limited" use. How are the use of these tools limited with these licenses?

[DanPatterson_Retired · Accepted solution]

well with example you gave, it is stated in the help file

License:

With ArcGIS for Desktop Basic and Standard licenses, the number of input feature classes or layers is limited to two.

with an advanced license you can use more than 2 layers or feature class all at once

[ChrisDonohue__GISP]

In explanation for Union their is this statement:

License:

With ArcGIS for Desktop Basic and Standard licenses, the number of input feature classes or layers is limited to two.

So for example if you wanted to Union 40 feature classes, you can't do them all in one shot.

Edit - Dan Ninja'd me again 

Chris Donohue, GISP