Expertise and reputation
If you can see that the website is supported by a reputable organisation or contributed to by a person with known expertise then it is reasonable to accept the website as being reliable. Examples would be where a website giving medical advice was run by a government department or a well respected charity eg. NHS direct at http://www.nhsdirect.nhs.uk/ or Cancer Research UK at http://www.cancerresearchuk.org/
Another more trivial example is that you would expect to find reliable recipes at Delia Smith's website http://www.deliaonline.com/
Now let's have a look at Lack of bias...
