What should go in the side column of a two-column resume?

Put short, list-style information in the side column: things a reader looks up rather than reads in depth.

Good sidebar content:

• Contact details (also keep your name and email near the top of the page).
• Languages with levels, for example: "English: fluent; Arabic: native".
• Key skills or tools as short words or phrases.
• Certifications with the year.
• Links, such as a portfolio or professional profile.

Keep each item brief, ideally one line. If an item needs a sentence to explain it, it belongs in the main column. A sidebar works best when the reader can glance at it and find a fact immediately.

Example sidebar for a hotel front desk agent: email, phone and city; languages (English, Arabic, Tagalog); systems (Opera PMS, Excel); and a first aid certificate with its year. Everything else, including the summary and each role's achievements, stays in the main column, where it has room to be read properly.