Why do we allow American English on spell checker?

Because Tesco isn't a real word, it's the name of a company so it isn't in the dictionary.

But yeah, we are being taken over a bit - when I was doing my exams earlier this year, I did chemistry and they have changed the spelling of 'Sulphur' to the American spelling 'Sulfur' on exam papers.

I had 2 minutes spare at the end so I crossed it out and wrote it correctly. - Most people probably wouldn't be bothered, but my name is Sophie, so if we're changing 'ph' words to the american 'f' now, I'd have to be Sofie instead. No way.

EDIT: Some people above are going on about the majority of Engliush speakers being american or whatever... but we are on the UK yahoo answers. So the spell check should by default be UK English. If you want american spellings, use the american website (.com)

You don't speak "real" English. You speak "British" English. "American" English is just as real. Don't be so bloody daft. Something which you seem not to comprehend is that language changes and evolves. Yes, even your British English. Ever heard of a chappie named Shakespeare? I do believe, old boy, that your British English has changed, even the spellings, since then. Latin is the only dead language that I know (I'm sure there are other, less obvious ones). If you're looking for sympathy by calling something you don't like "wrong," then you're being as close-minded as the stereotypical American! Of course, there is no American spelling like "offencive." Either the program has a glitch or a clear mistake that someone didn't catch.

Tesco is a proper noun and as such may not even be in an English dictionary (spell checker)

Colour, Centre, theatre and words that the Americans insist on using z instead of s are good tests.

I live in Canada, so I`m more accustomed to using British spelling than American spelling. I basically just ignore Y!A's spell checker because I have my own Canadian English spell checker running in the background.

While I live in the US for the time being, I grew up in Norway where we were taught the Queen's Own English. I bump into that problem all the time with words like "civilised", "worshipping", "colour", "labour" and many others.

I, too, ignore it most of the time. Especially if the American English spelling escapes me at the moment.

Handy note: The Almighty Yamster does not filter/block "obscene" words in Norwegian though his spell check minions will attempt to guess what you're trying to spell and "correct" you. *snert!*

It is because Yahoo as a company was headquartered in Sunnyvale, California in The United States of America, so they used American English in the spellcheckers.

"I did chemistry and they have changed the spelling of 'Sulphur' to the American spelling 'Sulfur' on exam papers." You are wrong. "Sulfur" is Latin, while "Sulphur" is in the original Greek, and has nothing to do with American vs. British spellings!

Whoever gave me a thumbs down better take it back!

It is democracy -- majority rule. Spell checkers are set up to benefit the most number of people, and not to cater to any specific minority group. Since the majority of English speakers use American spelling, then the default for spell checkers will be American English. It is the fair way :D

No idea but it shouldn't be allowed. Were english so the english language is ours. Americans should make there own or something and go away,

It's because Yahoo is American and being the arrogant bastards that they are if you don't do it the American way you are a nobody.

Its annoying. If it wasnt for the British dey wud still be living in mud huts.