People mix them up all the time. 'Can you translate for me at the meeting?' Sure, but what you actually need is an interpreter. Here is the practical difference, when you need which, and why it matters.
The short version
Interpreters work with the spoken word, in real time. Translators work with written text, at their own pace. If your conference needs live multilingual communication, you need an interpreter. If your contract needs to exist in another language, you need a translator. Different training, different skills, different tools.
Interpreting: modes and use cases
Simultaneous interpreting happens in real time from a booth with headsets. Consecutive interpreting involves the speaker pausing while the interpreter delivers the rendition. Whispered interpreting (chuchotage) serves one or two people without equipment. Each mode suits different settings: conferences, negotiations, court hearings, medical appointments, factory tours.
Translation: process and use cases
Translators take a source document and produce a target-language version. They use CAT tools (computer-assisted translation), terminology databases, and multiple revision rounds. Turnaround depends on volume and complexity: a standard business document might take a day, a technical manual several weeks. Typical assignments include contracts, annual reports, websites, patents, and marketing materials.
Can one person do both?
Technically yes, practically rarely. The skill sets overlap (deep language knowledge, cultural fluency) but the execution is fundamentally different. Interpreting is live performance under pressure; translation is careful, iterative craft. Most professionals specialise in one or the other. I am an interpreter. For translation projects, I am happy to refer you to excellent colleagues.
Which one do you need?
Ask yourself: is the communication happening in real time? If yes, you need an interpreter. Is it a document that needs to exist in another language? Then you need a translator. Hybrid scenarios exist too: a webinar with live interpreting and a translated slide deck afterwards. In that case, you need both. I can help you figure out the right setup.