The funeral yesterday of another Emmerdale star, Clive Hornby, was perhaps a less public affair, but Hornby – who played Jack Sugden in the ITV1 soap – will be equally missed, not only by his friends and colleagues in the show, but the millions of viewers who have watched him during the past 28 years. Soap stars and their characters hold a special place in the nation's heart, whether it's the dodgy antics of Dirty Den in EastEnders, or Bet Lynch and her blonde beehive over at the Rovers Return in Coronation Street. In many cases, the characters themselves are more famous than the people who play them, to the point where some fans can no longer tell the difference between the two. So when Deirdre Barlow found herself in the dock in Corrie, some of the show's most loyal viewers launched a campaign to free the Weatherfield One.

TV soaps live or die on the strength of their characters and the likes of Jack Sugden, Pauline Fowler and Vera Duckworth have kept generations of viewers enthralled with their domestic dramas and crises.

Kate Dunn, curatorial assistant at Bradford's National Media Museum, says viewers empathise with characters in soaps: "The characters that tend to have the most enduring appeal are often those that have a sense of humour, like Bet Lynch. A lot of people have been watching them from the start and develop a real affection for their favourite characters, which is why they're sorry to see them leave." Dunn believes the appeal of soaps lies in their mixture of comedy and realism. "Viewers are loyal to soaps because they become part of their everyday lives. They watch these characters three or four days a week, for months and often years, and after a while begin thinking they know them. I remember watching a Coronation Street documentary and Liz Dawn was saying that people come up to her in the street and ask how Jack (Duckworth) is and she plays along with it saying he's fine and looking after his pigeons. But it shows how real these characters are to a lot of people."

Many characters, such as Benny from Crossroads, are still talked about long after the show has finished, while others simply fade from the memory. Soaps, though, thrive on characters fighting each other, which is why the long-running feuds between Ken Barlow and Mike Baldwin, or the shenanigans of the Mitchell brothers, the pantomime villains in EastEnders, make such compulsive viewing.

"Everybody loves a villain and sometimes these characters are just as popular. You can't think of 'Dirty Den', for instance, without thinking of Angie, it was their relationship and the fantastic dialogue between them that helped make them such memorable characters," says Dunn. "There's something reassuring about soap characters, people identify with them and the problems they face. So when someone leaves after a long time it can leave a hole in people's viewing lives. There is also a sense that no matter how bad things may seem in someone's life there are people worse off and soaps remind them of this."

For some actors, though, being a soap celebrity sometimes comes at a price. "If someone has played the same role for 30 or 40 years it can be very strange to see them doing anything else. So a lot of soap stars find it difficult to do other work because people associate them with one character which becomes impossible to escape.

"Even with someone like Ross Kemp, quite often the characters he plays are in a similar mould to Grant Mitchell and it can be hard to escape that mantle."

Although the storylines have become increasingly controversial, with scriptwriters including everything from rape to domestic violence and, in Brookside's case, even incest, our appetite for soaps remains undiminished. "Although some of the past storylines were a bit melodramatic, I think TV soaps in this country are grounded in real issues which are reflected in the characters, and there's no sign that people are ready to give them up just yet."