Your new autobiography, Small Man in a Book, ends just as you become successful. Why?

It was a good dramatic point to end, at the age of 35, at the British Comedy Awards, which I used to watch year in, year out. When I first became successful, I was surprised people talked about my struggle. Being on the inside looking out, I didn't see it that way. Now I see it - with the way I was scraping along and how much debt I was in, if I were looking at it from the outside, I'd say, "Maybe it's not for you."

Was there a moment when it all went right?

I made the decision to leave college and work in radio, which sent me off that road. I often wonder where I would be now, if I'd not done that.

You starred in The Trip with Steve Coogan. Who had the harder role?

I think Steve's is more attractive - it's more dramatic, more introspective. But lightness is underestimated, in my opinion.

Why did that show work so well?

The age thing was very important; we were 45, starting to feel the effects of middle age on our body. And the slow pace - Michael [Winterbottom, director] is remarkable. Of all the creative people I've known, he has least regard for his audience, in a good way: he just tells his story.

Have you seen Coogan's campaign on phone-hacking and the tabloids - and his attacks on the Daily Mail's editor, Paul Dacre?

Of course. And the Mail followed it up, with the most awful photo of Steve it is possible to find. I love the choosing of photographs in newspaper articles. It's laughable, but people eat it up.

Did you see him thundering on Newsnight?

I did. Whatever you think of Steve, and I'd be the first to say he's objectionable on many levels, he stands up for what he believes in. It's remarkable to watch someone like [the ex-News of the World executive] Paul McMullan, who said: “If we catch a few corporate wrongdoers then you're a price worth paying." Whoa! What, a few innocents get killed? No! "You're happy to walk down the red carpet . . . you should be happy to be hacked." It's like saying: "You were happy to get into the taxi driver's car; he took you to Deptford where you wanted to go - yes, he assaulted you along the way, but it's a bit rich for you to complain." And there was so much envy in his tone. If you envy that, go and do it, Paul McMullan! Go and be an actor.

But some celebrities do play the system.

That's something else. We're talking about artists or performers. The others are marketing people, publicists, showmen. What I've never understood about some sections of the press [is] how you live with yourself knowing what you're doing is going to wilfully upset . . . people with feelings and families. We're not talking about war criminals here.

Do you ever wish you took more serious roles?

Not especially. I don't take that view of the dramatic inherently having more worth than the comic. I made a conscious decision about four years ago that I was just going to do what I liked.

Why is there snobbery about comedy?

Those people can fuck off. Only this morning I read on Twitter -

You don't read your @s, do you?

No. I stopped looking myself up. At its best, Twitter is a lovely community. At its worst, it's a megaphone for lunatics.

Are you tempted to reply?

I don't think I've ever succumbed. It comes back to not viewing you as a human being. You're that bloke on the telly; you're advertising breakfast cereal. The assumption is that you've got money coming out of your arse.

In the book, you talk about how the nature of laughter has changed since the 1970s and become more self-aware. Why has it?

Now, there are 57 channels and nothing on. Then, there was a gratitude that came from [knowing] we haven't got much choice here. That has to change the relationship to some degree between audience and performer, it has to.

Who are your influences?

I'm wary of someone who says, "I don't have any influences." Bollocks, you're just too up your own arse to admit that. We don't want to bang on about me, but certainly I can see all mine when I'm on stage: Ronnie Corbett, Barry Humphries, Dudley Moore, Jackie Mason, Woody Allen. Sometimes I feel like a big fraud.

Was there a plan for your career?

I wanted to be funny and entertain. That word's got a bad rap. I listened to Michael McIntyre talking about the stick he gets. People say, "Oh, he just points things out." Well, all right, you go and point things out.

Is there anything you regret?

Good lord, yes. A million things.

Are we all doomed?

Yes, we're all going to die. As a father, I feel bad saying that, as you always want to put a good face on for your kids. But it was ever thus.

Defining Moments

1965 Born in Swansea

1985 Leaves Royal Welsh College of Music and Drama for a job at Radio Wales

1989 Moves to London. Becomes presenter of a home-shopping channel

2000 Co-writes Human Remains for BBC. Takes role of Keith in Marion and Geoff

2006 Marries second wife, Claire Holland

2007 Returns to South Wales as Uncle Bryn in the breakthrough Gavin and Stacey

2010 Stars in The Trip with Steve Coogan