As often happens in the computer industry, nomenclature is unwieldy and flexible as technologists, sales & marketing, and the rest of the world clash.
My case in point is the phrase "data loss prevention" or DLP. In other articles, I have talked about DLP as a technology -- in that it is used to analyze the content of a document or message, determine whether the content references a concept confidential or protected in nature, and uses rules or reporting to handle the content. As the concept of DLP was developed in the last decade, the industry struggled to find an appropriate phrase that defined it: phrases including content monitoring & filtering, content analysis, deep packet inspection, and others were used, but the industry and analysts settled on data loss prevention.
Many companies are marketing "data loss prevention" in relation to their technologies, but not in the context of analysis of document content. Instead, their approaches include building a wall around all corporate data (such as on a mobile device, or in a cloud-based document-sharing service), or providing some regular expression matching for message content. This is well and good, but I would suggest these technologies fall under the larger strategy of information protection rather than being specifically about "data loss prevention".
This goes to the heart of the matter: when we build true data loss prevention systems, the intent is to protect confidential information rather than just bits and bytes of raw data. Under the fundamentals of information theory, data is just bits and bytes, but information is found where there is entropy, or value, in the data. This is what distinguishes data loss prevention technology from other data protection technologies, and perhaps the better phrase for the technology would be "information loss protection."
Practically, though, we are probably stuck with the labels that have been adopted. So, I suppose we can accept a variety of technologies under the strategy of data loss prevention, including the technology of data loss prevention itself. Unfortunately, this will continue to be confusing to those inside and outside of the industry and troublesome for sales and marketing.