What is it?

• The Beating the Retreat’ is a centuries-old military tradition dating from the days when troops disengaged from battle at sunset. 
• As soon as the buglers sounded the retreat, the troops ceased fighting, sheathed their arms and withdrew from the battlefield. It is for this reason that the custom of standing still during the sounding of retreat has been retained to this day. 
• Colours and standards are cased and flags lowered at retreats. Drumbeats recall the days when troops, lodged in towns and cities, were recalled to their quarters at an appointed time in the evening. 
• Beating the Retreat also marks the last ceremony of the nation’s Republic Day celebrations, which started on January 23 with Prime Minister Narendra Modi unveiling the hologram statue of Netaji Subhas Chandra Bose at India Gate.

Why in News?

• A thousand drones will dazzle the sky above Delhi for the first time ever, as part of a drone show which will be the highlight of the Beating Retreat ceremony. For the first time, the drone show has been made a part of the ceremony to commemorate 75 years of Independence, being celebrated as ‘Azadi ka Amrit Mahotsav.
• The drone show has been organised by a startup ‘Botlab Dynamics’ and supported by Indian Institute of Technology, Delhi and Department of Science and Technology. 
• The show would be of 10 minutes duration involving around one thousand drones fabricated through indigenous technology. 

Reference:

1. https://newsonair.gov.in/News?title=Beating-the-Retreat-ceremony-underway-at-historic-Vijay-Chowk&id=434388