Bollywood megastar Amitabh Bachchan recalled working on 10-15 films simultaneously, which required the actors to film several projects on the same day.Bachchan, who has been in the film industry for over five decades, said for him the word “prep ” used to be nothing but “an unknown entity.” The actor shared the pictures from the set on his personal blog on Friday and attached a note.”The prep was word or an explanation unknown to my generation and beyond ..now ‘it is’ a common vocabulary , where one prepares for the work to be undertaken .. for me it was an unknown entity .. i see now the amount of labour and pain, creative artists put in to get into the character, in looks and style and comprehensive character analysis,” he said.”A most valid and thought full act, and my admiration to those that are able to give this aspect the more than required serious consideration and be in preparation for the work, undertaken ..Good and impressive ..But in the good old’ days when we all worked in 10 to 15 films at the sme time – many two or three the same day , it would have been impossible to prep for one and the un prep for the other ..ON THE SAME DAY,” he added.The actor said it used to be the directors or assistants who would explain the scenes when the actors would reach the shooting location,” he added.Bachchan made his acting debut in 1969 with “Saat Hindustani”. He later went on to feature in several projects, including “Sholay”, “Zanjeer” and “Don”, among others. He has starred in over 200 films.The actor will next feature in the sequel to “Kalki 2898 AD” and “Section 84”, where he will appear alongside Diana Penty and Nimrat Kaur.