At its most basic it is simply typing out what you speak.
With this basic premise of writing in mind, there is no reason why anyone who can speak decent English cannot write some decent content.
I do not want to get into a primer on proper English, or on how to write, we will save that for another time, but let's take a look into how content is created today for websites whether it be for content, or for articles and informative stories.
Most webmasters today will gather some information first.
Taking notes as they go, creating a file full of notes and ideas.
I like to use this method and then sit back and read everything I have made notes of over and then expand on the sentences making sure to use my own words.
At this point I usually will then look for more sources of information and get some facts and figures.
While I am reading the material over, and writing out my own sentences I will come up with questions.
I research more to get answers and make more notes.
I will repeat this procedure incorporating new information, facts, figures and ideas until I have successfully completed an informative article that meets a need or has a purpose.
It's always good at this point to just type out some thoughts of your own to add to your research.
Since you have just spent some time learning about whatever it is you have chose to write about, you have a head full of ideas.
Write it out.
This is how valuable unique content winds up as a good informative article.
As long as you can generate a truthful, concise and readable story you will be fine for generating content.
For the vast majority of you, this will be information that you already know a great deal about...
you are writing for your own website or business and you can simply think as you type to generate great web content.