Mumbai, Jul 18 (IANS): For some he defined romance on screen, for some his heart-warming performances brought tears, and for a whole lot of Bollywood celebrities Rajesh Khanna, Hindi cinema's "first superstar", was the "phenomenon" whose "magic" will live on forever through his memorable films, dialogues and songs.

Young and veteran - celebrities of all age groups remembered Rajesh Khanna, fondly called 'Kaka', who passed away here Wednesday following prolonged illness.

Many of them took to Twitter to share their experiences and thoughts about the 69-year-old, who delivered hits like "Anand", "Kati Patang" and "Aradhana" among about 160 films that he featured in.

Here's what celebrities had to say:

Anupam Kher: Rajesh Khanna gave us a crash course in romance. He introduced us to a special twinkle in the eyeS that made us feel good about ourselves. Rajesh Khanna taught us how to smile. He added dignity to our concept of Romance. His songs made us forget our daily struggles of life. Rajesh Khanna was larger than life. He was a King who gave Indian Cinema glamour, style, and substance. We will Miss you Sir. RIP.

Madhuri Dixit-Nene: Another of Hindi cinema's giants passes, Rajesh Khanna. Our sincere condolences to his family. We will miss him dearly.

Shilpa Shetty: Just heard the sad news. Heartfelt condolences and prayers to the family to cope with this irreparable loss. R.I.P Rajesh Khanna, a superstar always.

Karan Johar: The magic, the mannerism, the mania of RAJESH KHANNA is inscribed in every archive of Indian cinema...forever...RIP SIR!!!

Rituparno Ghosh: You were the first to combine heroism and humanity in Hindi films. You were the Cupid who taught us romance. In a dhoti and kurta, you showed the rest of India how truly elegant Bengal was. Without you the screen will be robbed of much of its silver.

Kunal Kohli: The word superstar was used first for Rajesh Khanna. His style. His ada. His charm. His smile. His songs. His films. He. Will always live on

Prateik: Zindagi ka safar, hai yeh kaisa safar, koi samjha nahi.. - aap shayad samajh gaye. RIP Rajesh Khanna Sahab... upar Smita se zaroor milna (Do meet Smita Patil up there).

Madhur Bhandarkar: The epitome of superstardom is no more amongst us. There was none, there is none and there won't be any like you Kakaji. You will be missed.

Rahul Bose: RIP Rajesh Khanna. The Phenomenon. Thank you for the magic.

Mahesh Bhatt: When we lose a loved one, something within us dies. Our generation loved Rajesh Khanna. Today, a bit of us dies with this enigmatic star.

Vishal Dadlani: Hoping that the news of Rajesh Khanna's passing is another hoax. If it's true, we've lost India's first PHENOMENON, a true megastar! Rajesh Khanna inaugurated a park in Khar, in the 1970s. It's still called RAJESH KHANNA GARDEN! Always will be! Official name became irrelevant!

Ken Ghosh: RIP Rajesh Khanna - my first memory of a film theatre was weeping while watching "Haathi Mere Saathi".

Tusshar Kapoor: Rajesh Khannaji, our first superstar is no more! I worked with him in 'Kyaa Dil Ne Kaha' & learnt a lot just talking to him! May his soul RIP!

Shreyas Talpade: My first film that I saw on a VCR was 'Aradhana'. Zindagi kaisi hai paheli haaye, kabhi ye hasaye kabhi ye rulaye. RIP our very dear 'ANAND'

Divya Dutta: RIP Rajesh Khanna! The very endearing superstar of Indian cinema who brought romance a new meaning on screen! You'll be terribly missed Kakaji.

Dia Mirza: "Babumoshai eto bhalo bhasha bhalo na..."... "Anand", "Kati Patang", "Bawarchi" and many more... What a legacy you've left behind. RIP Rajesh Khannaji.

Pooja Bedi: Deeply saddened to know Rajesh Khanna is no more with us on this planet! Wish the family and all his ardent fans strength!

Manoj Bajpayee: Nafrat ki duniya ko chod ke pyar ki duniya me khush rahena mere yaar!Still remember "Haathi Mere Saathi". Saw it as a child. We will miss you sir.

It was an Honour to Sing for Rajesh Khanna: Manna Dey

Expressing grief over the demise of actor Rajesh Khanna, legendary singer Manna Dey Wednesday said he was honoured to have sung for the "first superstar" of Bollywood.

"He was a great actor, truly a superstar no doubt about it. I am honoured to have done playback for him. I have worked for him in several movies and actors like him are a rarity," said the nonagenarian Dey.

For Rajesh Khanna, Dey had sung songs "Zindagi kaisi hai paheli" ("Anand", 1971), "Tum bin jeewan kaisa jeewan" ("Bawarchi", 1972), "Hansne ki chah ne kitna mujhe" ("Avishkaar", 1973) and "Gori tori paijaniya" ("Mehbooba", 1976).

"Working with him had been a memorable experience for me. All the songs that I have sung for him have been hits, especially songs from 'Anand' and 'Bawarchi'. We used to meet at functions. He was a very nice person to talk to and be friends with," said Dey.

"I loved the way he picturised music. The success of a song depends upon how an actor picturises it. He was the number one in picturising songs. I will be ever indebted to him," said the singer whose song "Zindagi kaisi hai paheli" for Rajesh Khanna in "Anand" has been a memorable hit.

Rajesh Khanna passed away Wednesday following prolonged illness. He was 69.

We thought he would come Back: Hema Malini

Veteran actress Hema Malini is in shock after hearing about the demise of Rajesh Khanna and says she always hoped that he would recover.

"We always thought he would come back (from the hospital). We are in shock right now," Hema told a TV news channel.

Rajesh Khanna died at his Bandra residence Wednesday after a prolonged illness. He was 69.

Talking about her last meeting with the superstar, the actress said: "We met at Apsara Awards, at the celebration of 100 years of cinema. He spoke to us and he talked properly and looked fine."

The two worked together in films like "Andaz" and "Prem Nagar" and Hema says the news is sad and she will soon meet his family members.

"I have worked with him in many films but right now this is a very sad moment and I must go and meet his family members," she said.