Compared
Thesis or course-based master's: which changes your application?
The short answer
A thesis-based master's is research training, usually needs a supervisor to agree before admission, and is where funding lives. A course-based master's is a taught professional qualification admitted by committee. The distinction decides what your statement argues, and writing the research version for a taught programme is a common structural error.
What changes in the application
Thesis-based: name two or three faculty whose recent work you have read, state a problem, evidence the methods you can already use. Contacting a potential supervisor before the deadline is often part of the application rather than optional, as set out in how to email a supervisor.
Course-based: name the modules, the specialisation stream, the capstone or placement, and the professional outcome. A research-heavy statement here reads as a misunderstanding of what you applied to.
Funding follows the thesis
Assistantships and supervisor-held funding attach to research programmes. Course-based master's programmes are usually self-funded, which is a material difference when comparing offers. See assistantship and tuition waiver.
Which one you should want
A thesis route if you intend to continue to a doctorate, or want funding, or want research training. A taught route if you want a qualification for a specific job in a defined time. Neither is more prestigious; they lead different places.
Related questions
How do I know if a programme is thesis or course-based?
The programme page states it, usually under structure or degree requirements, and the naming is often explicit: MASc and MSc by research are thesis-based, MEng and most taught MSc programmes are not. Checking takes five minutes and changes what the entire statement should argue.