I get about 2-3 emails asking about applying to the HCDE or MHCI+D masters programs each day. That is more than I can reasonably answer while honoring commitments to students who are currently in our programs.
In this page, I try to summarize the most frequently asked questions and my perspective. Note that these are my perspecives and I do not speak for the entire faculty or staff, especially about what makes for a strong application.
They are both great! Before getting into the differences, both programs are key parts of our human computer interaction and human centered design community at UW. If you join either, you'll see people from programs around campus, particularly if you see out opportunities like the DUB seminar series.
For the differences, you can inspect the curricula for each online. In addition to specific courses, don't underestimate the structural differences. MHCI+D is an intense, year-long, cohort based program. You'll spend a lot of time in studio with your cohort, staff, and instructors. For some students, that really helps you thrive, while for others, it's a little too claustrophobic. In constrast, HCDE can be a full-time program, but it also can be spread out to accomodate concurrent employment. The program is larger, so you'll meet more people and have less strong of a cohort experience.
Additionally, HCDE includes for-credit, directed research groups which will give you hands-on experience with research in the field (it is not, however, a research-oriented degree!).
It may be that each offers advantages for you, and it's okay to apply to both. Your statement for each program, though, should reflect that program -- we want to make sure the program, not just UW overall, is a fit for you.
All of the HCI / HCDE masters programs at UW are deliberately diverse. The main things that I look when I read applications are:
In between (1) and (2) is a need for students to not be over-prepared. An HCDE masters degree is a lot of time and money, and we want to make sure that admitted students get a lot of out of the program. So, will the program build in your prior preparation enough to be worth the investment of your time and money? If you are a student with an HCI, informatics, HCDE, or related undergraduate degree or professional experience, it will be particularly important that you specifically articulate what you expect to gain from the program.
Note: HCDE no longer has a space to submit one for 2020. I still encourage you to include a link to a website talking about your best projects as part of your materials, e.g., on your résumé.
Even if you are not from a field in which portfolio production is part of the standard professional training or education, you should be able to pick 2-3 projects from your education or work experience and discuss how they relate to human centered design. A simple web page with some reflection (and visuals, if possible!) will give us much more insight into how you work.
Overall, the strongest portfolios show both process and outcomes and demonstrate some reflection on what you learned from the experience. If your portfolio includes group projects, it is important that it articulate your role in those projects.