Ram Navami is a famous Hindu Festival, which marks the birth of Lord Rama at Ayodhya (India) to King Dasharath and Queen Kausalya. Lord Rama was another Avatar for Lord Vishnu and the Holy Book of Ramayana is mainly based upon life of Lord Rama and Kingdom of Ayodhya.
Rama Navami is celebrated on the ninth day of chaitra month as per Hindu Calendar, which is also the ninth day of Navratri. It falls in the month of March/April every year, this year in 2018, it would be celebrated on 25th March 2018, while Navratri starts from 18th March 2018.
The ninth day of Navratri festival is celebrated as Ram Navami with joy and fervor, not only in India but by Hindus all around the world. It is an auspicious day, where devotees observe fasting (vrat), seeking blessings of Lord Rama. The temples are decorated and the puja/aarti is performed seeking blessings and good luck, which is followed by distribution of prasadam (sweets).
It is celeberated with more zeal and enthusiasm at Ayodhya (Uttar Pradesh), Janakpurdham (Nepal), Sita Samahit Sthal (Sitamarhi, Bihar), Kodandarama Temple Bengaluru), Bhadrachalam (Telangana), Vontimitta (Andhra Pradesh) and also at one of the most famous temples Rameswaram (Tamil Nadu).