Navratri is a festival that lasts for 9 days (and literally means 9 nights). There are 3 days devoted to worship of Durga (the Goddess of Valor), 3 days devoted to the worship of Lakshmi (the Goddess of wealth) and 3 days devoted to the worship of Saraswati (the Goddess of Knowledge).
During these nine days, feasting and fasting take place. There are many festival activities that take place in the evenings as well.
Please pray for the Christians of Delhi during this holiday. Pray that they don't hide away in their homes while this holiday is going on. Pray that they are bold in sharing their faith with those around them!