Draft document
In the context of written composition, drafting refers to any process of generating preliminary versions of a written work. Drafting happens at any stage of the writing process as writers generate trial versions of the text they're developing.  At the phrasal level, these versions may last less than a second, as writers compose and then delete trial sentences; as fully developed attempts that have reached the end of a stage of usefulness, draft documents may last for perpetuity as saved "versions" or as paper files in archives.
Background of Draft Writing and Some Effects
Draft Writing, we are used to the annoying step we continuously have to do when we have a big paper, we have to revise, we plan our thoughts. We write in so many different scenarios, but as writers, we don't realize how impactful it is to our process of writing. Typically, one should be used to writing multiple drafts until finally having their paper finalized. It may take a couple of drafts, but even though it may be difficult to start, it generally helps improve better than the other draft.
Young students are taught this way, according to much research because it helps students make it easier for them to write something. It helps them build up skills to grow into developing more skills. Skills take time to grow, if students start at a young age, it can make them a strong writer once their education levels are higher.In a book that became popular in the 1950s, The Elements of Style, Strunk and White characterize a first draft as a less-edited version of the final draft with the purpose of "foresee[ing]...the shape of what is to come and pursue that shape". In Writing Without Teachers, a more recent take on the role of draft documents, Peter Elbow characterizes a draft less as a first attempt at a predetermined final point and more as an attempt at exploring and where a final version might end up.  As he puts it, “[w]riting is a way to end up thinking something you couldn’t have started out thinking.” According to Elbow, the best way to accomplish this is a series of drafts which come together to produce an emerging “center of gravity” that then translates into the main focus on the work—a holistic process, in other words, rather than the linear process envisioned by Strunk and White and early writing process theory.  Elbow reasoned that if a writer "learns to maximize the interaction" among their "ideas or points of view, [they] can produce new ones that didn’t seem available."Empirical studies of writers at work indicate that writers can be doing any or all of the following during phases of drafting:

developing cohesion
organizing their thinking in relation to text produced so far
experimenting with phrasing
explaining or linking examples/ideas
generating transitions
discovering a central argument/point
elaborating on key ideas
pausing to make adjustments to spelling, word-choice, and syntax

Mindset of drafting
In drafting, students cannot be scared of failure. Through failure in ugly drafts, it allows experimentation without penalty (Bohney). The more the writer drafts, it allows them to see what works and doesn't work for their writing. In a bad draft, the writer can reflect on the problems and grow from the mistakes. Mistakes are necessary and it does not mean their writing is poor, but it means they are finding ways to make their writing better. As Brandie Bohney in Fail Forward!states , Mistakes are a “success as long as you learn from it”.

Computers vs pen and paper
With technology, most writing is done on computers. Unlike with pen and paper, computers make it easier to compose new drafts (Dave). Computer software that has word processing makes it easier to fix local, grammar and spelling errors.
Although, drafting on a computer does not signify better drafts. Before word processing, when students created a new draft, it was an investment of their time dedicated to completely rewriting the entirety of their essay. This dedication influenced global revisions, stated in Draft and revision using word processing by undergraduate student writers. When using word processors, it causes students to only correct minor grammar mistakes the computer points out and miss global mistakes. In comparison to when students create physical, handwritten drafts, they have to constantly reread/ revisit their essay, making more corrections based on ideas.  
In order to benefit from both, it is possible to type drafts on a computer and then print it to make physical revisions. By typing on a computer, it allows the writer to fix the minor mistakes the word processor points and revise the printed copy, it also allows the writer to make global revisions (Becker). Thanks to the computer, the process of drafting which includes creating numerous drafts, can save the writer time instead of having to physically rewrite the entirety of their drafts.

Relationship between drafting and revising
When drafting, a major part of the process is allowing others to revise the work. Through revision, it allows others to give the writer feedback to make corrections. Revising the draft is not the same as proofreading, since it is not just fixing spelling mistakes, it is re-imagining the goals and looking at it with a different scope. Revision causes the writer to fix sentence structures and possibly rewrite the entirety of the draft (Dave). As Anne Becker states in A review of writing model research based on cognitive process, professional writers use revision in every step of drafting. It is a time consuming process that involves trial and error.

Multi draft composition
Multi draft composition involves four stages of writing which include planning, drafting, revising and editing. In the curriculum, students are often required to compose at least three unique compositions like research, persuasion and analysis (Owens). In multi drafting, there are frequent large-scale changes on paper causing writers to create numerous drafts. It emphasizes repeating the steps, and continuously going over it, improving the content and organization. This composition is often taught to ESL writers and is open to writing types across different genres. There is no fixed form as it focuses on the end purpose, according to Kim Owens in Teaching the six-and beyond, “drafting is an investment, you get out if it what you put in”.

See also
Draft (music)
Foul papers
Manuscript format
Rough ASCII
Sketch (drawing), a similar concept, but for visual arts

References
Eckstein, Grant, Jessica Chariton, Robb Mark McCollum. (2011). Multi-draft composing: An iterative model for academic argument writing. Journal of English for Academic Purposes 10.3, 162-172.

Further reading
Dave, Anish; David R. Russell. (2010). Drafting and revision using word processing by undergraduate student writers: Changing conceptions and practices. Research in the Teaching of English 44.4, 406-434.
Owens, Kim Hensley. “Teaching ‘the Six’-and Beyond.” Pedagogy : critical approaches to teaching literature, language, culture, and composition 9.3 (2009): 389–397. Web.
Bohney, Brandie (Guest Editor). (2018). Fail Forward! [Teacher to Teacher column]. Journal of Teaching Writing 33.2, 65-66.
Becker, Anne. (2006). A review of writing model research based on cognitive processes. In Horning, Alice; Anne Becker (Eds.), Revision: History, theory, and practice; (Reference guides to rhetoric and composition); West Lafayette, IN: Parlor Press (pp. 25-49).
"The Writing Process: Study Hall Composition #1: ASU + Crash Course." YouTube, YouTube, 31 Mar. 2020, https://www.youtube.com/watch?v=AXa22Csh7oE.