In a grad school application, there can be several different essay requirements. You might see them called “Statement of Purpose” or “Personal Statement”. Sometimes they provide a few bullet points for what topics you should cover. Be warned! A “Personal Statement” for one school might differ dramatically from another school’s idea of a “Personal Statement”. Look at each school’s specific requirements, even if they call the essay the same thing.
The purpose of these essays is usually twofold:
Does this candidate write well?
What can we learn about this candidate that’s not in any other material?
The questions will vary, but the goal for admissions committees is the same. That means that you should spend a significant amount of time thinking about what you will write about. After you write, have multiple people proofread it. Proofread it on separate days as well.
Grad school essays are also good places to highlight any information that you think the admissions committee should know about you. Maybe you had a difficult academic year for personal reasons, or you’re applying for something outside of your undergrad degree. In any case, an essay can explain your reasons and help a committee say yes to you.