Final answer:
The truncation feature allows users to search for variations of a keyword by indicating the root of a word and having the search engine return all results that include any extension of it.
Step-by-step explanation:
The truncation feature in search engines is used to find variations of a keyword. By using a specific symbol, often an asterisk (*), you can search for the root form of a word, and the search engine will return results that include any ending of that root word.
This can be especially useful in comprehensive research where you want to include all possible variations of a word to ensure you don't miss relevant information. For example, searching for 'comput*' could yield results for 'computer', 'computing', 'computation', and so on.