What is a context match relative to translation memory?

You will often hear language service providers talk about context matches. You may ask, how is that different from a 100% match?

We should first mention that most language service providers use translation memory technology to store human translations in a database to create consistency and savings on future projects where the same content is repeated. This is especially important for clients that update their documentation frequently.

So what is the difference between a 100% match and a context match? A 100% match is a sentence in a document that is identical to a previously translated sentence that is stored in the database. A context match is a 100% match that also has the same exact preceding sentence and subsequent sentence. This gives us a little more certainty of the pedigree of the 100% match.
The reasoning behind this confidence is that a 100% match in context is far better than a plain 100% match. I believe this is especially true for short segments.

Most translation memory management systems now differentiate between the two levels of 100% match.