is it important to use commas in the meta keywords?
What if I don't have the commas?
According to the W3 standards:
- Provide keywords and descriptions
- Some indexing engines look for META elements that define a comma-separated list of keywords/phrases, or that give a short description. Search engines may present these keywords as the result of a search. The value of the name attribute sought by a search engine is not defined by this specification.
In other words, it's not defined by the HTML standard what a meta with name="keywords" should look like. It all depends on what your targetting. Some search engines use commas in a keywords meta tag to separate keywords. Some ignore such meta tags completely.
What if I don't have the commas?
Then your keyword is the whole phrase together. So with keywords “lemon cake”, it won't match when you're searching merely for “lemon” or “cake”.
In reality meta-keywords is at best no more effective than simply having the words included in your page, and at worst totally ignored. So there's very little point using it.
Actually most searchengines ignore the keyword meta element. So actually you could just erase it and save som bytes... :P
I agree that you can probably just ignore the tag as for example Google does not use them. Yahoo however does seem to use it (at least at the end of 2007), so if you want some more information, I found this article an interesting read.
No, just space ... at least this works for me :)
来源：https://stackoverflow.com/questions/623554/html-meta-keywords-should-contain-commas