A British Royal wedding has been announced, and it is likely to be a huge event, with television coverage of the whole day and crowds sleeping overnight in London streets to get the best view of the procession.

Prince William, who is second in line to the throne, and his girlfriend Kate Middleton will marry in the spring or summer of 2011. Newspaper stories say the couple hope to marry in April, probably at Westminster Abbey.

Here's a quick guide to royal weddings:

• The last really big royal wedding was in 1981. It was the marriage of Prince William's mother and father, Prince Charles and Lady Diana Spencer. The world went mad for Lady Diana because she was just 19, shy, and very pretty. Diana became a royal superstar as a result.
  
  
• Princess Diana's wedding dress set the fashion for dresses. It had puffed sleeves, a frilly neckline and an enormous skirt. It also had a train of material behind which was 25 feet (about 10 metres) long. The wedding was shown live on television and was watched by millions of people. The day was declared a public holiday.
  
  
• Royal weddings are a fantastic spectacle. You can expect to see a formal procession through central London to the church (usually Westminster Abbey but sometimes St Paul's Cathedral) and back, which will include soldiers in fantastic uniforms, horses, carriages and marching bands. The current British Prime Minister, David Cameron, slept on the pavement near Buckingham Palace as a 15-year-old to get a good view of the Charles and Diana wedding the next day.
  
  
• The pressures of joining the Royal family are not good for marriage. All four of the Queen's children have married but three later divorced, and two have remarried. Princess Diana died in a car crash in Paris after her divorce from Prince Charles.
  
  
• Experts say the William/Kate wedding and engagement could be worth GBP 600m for the British economy. Souvenirs such as mugs are already in the shops, and tea towels, thimbles and other items are likely to arrive very soon. They will all have the initials W and C on them as Kate Middleton has said she wants to use her full name, which is Catherine.
  
  
• Teatowels (kitchen cloths used to dry plates and cups) have a special role in royal weddings. Princess Diana said she wanted to back out of her own wedding the night before the ceremony. She was told: "You can't – your face is on all the teatowels."
  
  
• Kate Middleton's sapphire and diamond engagement ring originally belonged to Princess Diana, Prince William's mother, and was worth GBP 28,000 in 1981. Shopping TV channel QVC has been selling a ring which looks similar for just GBP 35. Sales of the cheap ring have risen 800 per cent since the wedding was announced.
  
  
• When the Queen and Prince Philip married in 1947 it was not long after the end of the war. There were strict limits on the amounts of food and materials people could buy.
  
  
• Queen Victoria, who married in 1840, set the fashion for wedding dresses in Europe to be white or cream. Until then most royal brides had dresses of gold or silver cloth, which were too expensive for most people. Victoria chose a white dress, with flowers on her head. Any bride could have a white dress, and so a fashion was created. Whatever wedding dress is chosen by Kate Middleton will set a fashion.
  
  
• Traditionally, royal wedding rings are made with gold from Wales. This is quite rare. A single nugget was used in several wedding rings, and the Queen was then given another nugget for her family.

By Susan Young (susan@englishuk.com)