The document discusses zero-rating practices in Europe. It conducted a survey of 32 countries and 225 mobile operators, identifying 186 instances of net neutrality violations through practices like zero-rating and paid prioritization. Zero-rating is defined as providing unlimited data for specific apps/classes of apps, while application-specific data volumes only allow data usage for certain apps. The survey involved a team of six people across four months to comprehensively analyze differential pricing offers in European countries.