Difference between eqangle and eqangle6, eqratio and eqratio6.

I am trying to understand deduction rules and have the following question. 

In the file with rules https://github.com/google-deepmind/alphageometry/blob/main/rules.txt there are eqangle and eqangle6 notation, what is the difference between them? The same question for eqratio and eqratio6. 