Content writing?

     Content is the most important part of SEO because it's the content that represents your website to the user.It explains your work,what are your doing, how are you performing.     So writing content for website is the most crucial part of SEO. This content should be unique it shouldn't be copied from any other website.If it is copied google will ban your website.To see if your content is copied or not you can go to copyscape.com & paste the url of your website. Copyscape will scan the entire network to find any similar content on other website.
     Content writing for SEO should be done very carefully.The keyword density should be 3% to 4% of your entire content. You should not stuff extra keywords just to get good SERP doing this is considered illegal & comes under black hat seo technique.
      The keyword proximity should also be taken into consideration while doing SEO content writing.

         Content writing is a difficult part of SEO & getting a good seo content writer the most difficult. Hence it has highest weightage in SEO techniques.