What does Strawberry Perl change in Windows?

Hi,

I am wondering what changes does the Strawberry Perl installation do
to a windows system?
I noticed adding

C:\strawberry\c\bin;C:\strawberry\per\bin;C:\strawberry\per\site\bin;
to the Path

I also noticed there are two environment variables:

PERL_JSON_BACKEND = JSON::XS
PERL_YAML_BACKEND = YAML

but I am not sure if they were set by Strawberry or something else?
What are they needed for?

Are the other changes?

regards
   Gabor