Demi Moore, George Clooney, Oprah: Hollywood's humanitarian side

Amidst all the glitz, glamour and vacations on luxury yachts, Hollywood stars make time to do their bit for charity.

While Oscar winning actress Sandra Bullock has given away a significant chunk of her earnings for relief funds for the earthquake in Haiti, the December 2004 tsunami and to the American Red Cross, Angelina Jolie's long association with the United Nations is well known.

Here's a look at several Hollywood A-listers at their charitable best.

Demi Moore

Actress Demi Moore and Maiti Nepal Chairperson Anuradha Koirala arrive for a news conference organised at Maiti Nepal in Kathmandu.

Maiti Nepal is an organisation which aims to protect Nepali girls and women from crimes like domestic violence, trafficking for flesh trade, child prostitution, child labor and various forms of exploitation and torture. 

US actress and Unicef's Goodwill Ambassador Susan Sarandon feeds a child at a health care community centre in Magu District north of Tanzania in May.

Sarandon also visited AIDS orphans and several centers ran by UNICEF before heading to meet the Tanzanian President Benjamin Mkapa during her 2000 trip.

Iconic television show host Oprah Winfrey poses with high school students during her school's first graduation ceremony at the Oprah Winfrey Leadership for Girls at Henley-on-Klipk, outside Johannesburg in 2012. 

Actor-director Sean Penn holds an Egypt flag at Tahrir Square during a protest against the ruling military council, after Friday prayers in Cairo in September 2011.

Egyptian activists converged on downtown Cairo for a demonstration against ousted President Hosni Mubarak.

US Secretary of State John Kerry talks to actor George Clooney at the airport in Juba, south Sudan in January 2011, after his visit to assess the country's readiness for the referendum on independence.

Actress Mia Farrow, a UNICEF goodwill ambassador, smiles as she holds a Haitian baby during her visit to a shelter in the town of Gonaives in September 2008.

Haiti was blasted by four storms -- Hurricanes Gustav and Ike and Tropical Storms Fay and Hanna -- from August to September that year, killing hundreds and destroying homes and crops. 

Colombian pop star and the United Nations Children's Fund (UNICEF) ambassador, Shakira, embraces a child during her visit to the Max Payne Hand in Hand School for Bilingual Education in Jerusalem in June 2011.

Singer Madonna turns the soil to lay the foundation of a multi-million dollar girls' school she is building in Chinkota, outside Lilongewe in Malawi in October 2009.

Madonna, who has adopted two children from the southern African country also attended a brick-laying ceremony in Lilongwe. 

UNHCR (United Nations High Commissioner for Refugees) Special Envoy Angelina Jolie meets Syrian refugees in the Bekaa Valley, Lebanon in September this year in this UNHCR handout photograph.

David Beckham, in his role as UNICEF Goodwill Ambassador, is seen posing for a photograph with a local mother Tamara, who is living with HIV and her three year old son Sesiphi who was born free from HIV, during a visit to a clinic in Cape Town, South Africa in December 2009 handout photograph received in London.

During the visit Beckham met and talked to young pregnant women and new mothers who are living with HIV, and was informed on how the UNICEF 'Mothers to Mothers' (M2M) programme is supporting HIV positive pregnant women and new mums.