Role of Php on SEO

hey sorry guys if it 's off topic.I,m just curious to know from you guys that how important is that you have a good knowledge of PHP in SEO if you want to be good at SEO like if I want to go for blog creation, I have a good knowledge of HTML though but I want to learn PHP. So how many people here agree that PHP is important on SEO not only for developer but for people who are not familiar with web-design etc.And one more question is what are the other things that you should know before creating a blog..?

for a blog if run on wordpress PHP is quite useful but not very important... if you understand how to tweak permalinks and things like that you wont need to use php.

plus if u use wordpress you can just get plugins, i.e. other people write php code for you ;)

PHP server language and is not directly related to SEO, but the speed of page loading and placing the data in SEO optimized output is something that comes from knowing the basic principles of SEO...