Is editing the same thing as proofreading?

Surprise, It's totally different.

*Editing

Editing is what you begin doing as soon as you finish your first draft. You reread your draft to see, for example, whether the paper is well-organized, the transitions between paragraphs are smooth, and your evidence really backs up your argument. You can edit on content, structure, clarity and style.

*Proofreading

Proofreading is the final stage of the editing process, focusing on surface errors such as misspellings and mistakes in grammar and punctuation. You should proofread only after you have finished all of your other editing revisions.