Content strategy focuses on the planning, creation, delivery, and governance of content. Content not only includes the words on the page but also the images and multimedia that are used.
From Gov.uk's series on writing web content: People read differently on the web than they do on paper. This means that the best approach when writing for the web is different from writing for print.
Accessible forms are easy to understand, complete, and submit. Instructions, cues, required form fields, and field formatting requirements must be clearly identified to users. Error recovery must be intuitive and descriptive.