The Birth Anniversary of Lord Krishna who is the 8th incarnation of Lord Vishnu is celebrated as Janmashtami. This festival is celebrated on the 8th day of Krishna Paksh in the month of Bhadon which usually falls in the month of August / September. This Year, Shri Krishna Janmashtami is on Monday, 30th of August 2021.
Lord Krishna was born to Devaki and Vasudeva who were held captive by demon Kans since there was a prophecy that the Son of Devaki & Vasudeva will kill Kans who was the ruler of Mathura. However, all the guards went asleep and all the locks opened by themselves as soon as Lord Krishna was born thereby facilitating Vasudeva to take Lord Krishna to Nandgaon safely. Thereafter, Lord Krishna was brought up by Devi Yashoda (Wife of Shri Nand ji).
All during the time, while Lord Krishna was growing up as a child in Nandgao, he performed various acts of valour which are known as Krishna Lilas. Some of them being " Putna Vadh " (Killed female demon Putna who was sent by Kans to kill the Child Krishna), Vakrasur Vadh, Kaaliya Mardan ( Defeated the serpent Kaaliya who has captured and poisoned the water of river Yamuna ), Lifting of Govardhan Mountain to save the people of Nandgaon from wrath of Lord Indra and the famous Raas Lilas. Finally, he, along with his elder brother Balram, went to Mathura and killed Kans thereby freeing the people of Mathura from his demonic rule.Lord Krishna was very close to all the 5 Pandavas and his role in the battle of Maha Bharat was the key factor which tilted victory in favour of Pandavas.
In India, Janmashtami is celebrated with great fanfare and enthusiasm. People observe fast for the entire day and they visit Lord Krishna's Temples. In many cities of India, a game of "Dahi Handi" is arranged since Dahi (Curd) & Makkhan (Butter) were very favourite of Lord Krishna. In this game, Dahi ( Curd ) & Makkhan ( Butter ) are kept in a earthen pot along with prize money and it is suspended high, at times, even upto height of 20 to 40 feet from ground. Groups of players known as Gopalas form human pyramids so that the top most player can reach to the earthen pot and claim the prize money.
Lord Krishna taught us the importance of Karmas and he advocated the theory of Karma wherein we have an absolute control over our Karmas but their results and subsequent benefits / losses are in the hands of God depending upon the type of our Karmas.