Why is the Indian Constitution called the longest written constitution in the world?

The Indian Constitution is the longest written constitution in the world for several practical reasons. India is a vast, diverse country with many languages, religions and regions, so the framers wrote detailed provisions to address this diversity and prevent confusion. It contains the administration of both the Union and the states in a single document, unlike federations that keep them separate. It also borrowed good features from many constitutions around the world and included detailed Fundamental Rights, Directive Principles, and provisions for special groups and emergencies. The framers wanted to leave little to chance, having seen problems in other countries, so they spelt things out clearly. Originally it had 395 articles, 22 parts and 8 schedules, and it has grown through amendments. This detail makes it long but also makes its working clearer.