Examples of abbreviations Abbreviations are a common part of both formal and informal communication, and they come in many different forms. Here is a list of common abbreviations, categorized by type and usage. General & Everyday Use ASAP: As soon as possible FYI: For your information ETA: Estimated time of arrival DIY: Do it yourself TBD: To be determined TBA: To be announced N/A: Not applicable or not available E.g.: (from Latin exempli gratia) for example I.e.: (from Latin id est) that is; in other words Etc.: (from Latin et cetera) and so on; and other things P.S.: (from Latin post scriptum) written after; an afterthought Professional & Business B2B: Business-to-business B2C: Business-to-consumer CEO: Chief Executive Officer CFO: Chief Financial Officer HR: Human Resources KPI: Key Performance Indicator EOD: End of day WFH: Work from home NDA: Non-disclosure agreement SaaS: Software as a service ROI: Return on investment PR: Public relations RSVP: (from French répondez s'il vous plaît) please reply Internet & Texting Slang LOL: Laugh out loud BRB: Be right back BTW: By the way IMO/IMHO: In my opinion / In my humble opinion TL;DR: Too long; didn't read SMH: Shaking my head OMG: Oh my God / Oh my gosh IDK: I don't know ICYMI: In case you missed it DM: Direct message POV: Point of view Academic & Scientific PhD: Doctor of Philosophy BA/BS: Bachelor of Arts / Bachelor of Science M.D.: Doctor of Medicine DNA: Deoxyribonucleic acid MRI: Magnetic Resonance Imaging NASA: National Aeronautics and Space Administration UNESCO: United Nations Educational, Scientific and Cultural Organization Time & Dates AM/PM: (from Latin ante meridiem/post meridiem) before noon / after noon BC/AD: Before Christ / Anno Domini (in the year of the Lord) BCE/CE: Before Common Era / Common Era GMT: Greenwich Mean Time EST/PST: Eastern Standard Time / Pacific Standard Time