Final answer:
The two major functions of search engines are Indexing and Ranking, with the former cataloguing internet content and the latter organizing search results by relevancy. User awareness is crucial as search engine results can be influenced by SEO practices, hence not always displaying the most authoritative sources first.
Step-by-step explanation:
The two major functions of search engines are: a) Indexing and Ranking. Indexing refers to the process by which a search engine scans and catalogs the content available on the internet. Meanwhile, ranking involves ordering the search results based on relevancy to the user's query, which is determined by complex algorithms considering factors such as keyword frequency, website popularity, and interlinking amongst sites.
It is important to note that while using search engines, results are displayed with a variety of influences and may not always show the most authoritative or accurate information first. Companies and websites use search engine optimization (SEO) techniques to improve their visibility in search results, which calls for a critical eye when evaluating the information found through search engines.