The Passport Index is a global ranking system that evaluates the strength of passports based on the number of countries their holders can visit without a visa or with visa-on-arrival access. It provides a comprehensive overview of passport power, helping travelers understand their mobility options. This index is updated regularly and considers various factors, including diplomatic relations and visa agreements between countries. It serves as a useful tool for individuals, governments, and businesses to assess travel freedom and make informed decisions regarding international travel and immigration policies.