LONDON - The Queen, who celebrated her 60th wedding anniversary last month, said on Tuesday that the family was the core of society and urged greater consideration for the vulnerable and marginalised.

Marking the 50th anniversary of her first televised Christmas address to the nation, the Queen also paid tribute to dead and wounded members of the armed forces serving in Iraq and Afghanistan.

"For their families, Christmas will bring back sad memories, and I pray that all of you, who are missing those who are dear to you, will find strength and comfort in your families and friends," she said.

Noting the changes in her realm during her rule, the 81-year-old monarch for the first time also posted her annual address on the video-sharing website YouTube.

"To remember what happened 50 years ago means that it is possible to appreciate what has changed in the meantime. It also makes you aware of what has remained constant," she said.

"In my experience, the positive value of a happy family is one of the factors of human existence that has not changed.

"The immediate family of grandparents, parents and children, together with their extended family, is still the core of a thriving community," she said as her 1957 broadcast ran on a screen in the background.

A new Royal Channel has been created on YouTube, allowing Web surfers to view the Queen's first Christmas broadcast in 1957, as well as other archive footage of the royal family and its events.

The catalogue is at www.youtube.com/theroyalchannel.

The Queen, who writes the Christmas message herself and records it in one take, said all the world's great religions taught care and consideration for others less well off.

"For these people the modern world can seem a distant and hostile place," she said.

"Fortunately, there are many groups and individuals, often unsung and unrewarded, who are dedicated to ensuring that the 'outsiders' are given a chance to be recognised and respected.

"However, each one of us can also help by offering a little time, a talent or a possession, and taking a share in the responsibility for the well-being of those who feel excluded," she added.

"Wherever these words find you, and in whatever circumstances, I want to wish you all a blessed Christmas," she concluded.