(Putting your understanding of other people’s ideas and information into your own words)
Good academic writing depends on how well you bring together information and ideas from relevant publications into a whole that addresses the topic and supports your argument.
The ability to re-formulate what you read into your own words is critical, as not doing so can mean that you have, intentionally or not, plagiarised. This process is called paraphrasing, and it is, with correct citing and referencing, absolutely vital to successful writing.