What do snippet and SERP mean?
SERP is the acronym for "Search Engine Results Page".
This acronym is very often used in both English/American and French publications.
A snippet is an extract of a page displayed in the... SERP . This extract is located between the title of the page and its URL, or just below the URL.
Most of the time, it is the content of the meta description but Google reserves the right to display whatever they want.
If there is no meta description or if it judges that its content is not relevant regarding the user's search, then it would not hesitate to display a part of a text that comes from your content.
Considering that the page results is the initial contact with the internaut, you'd better spend time on your snippets in order to make sure they are good and make users want to visit your website, rather than the website of your competitors.
Moreover, the display of snippets frequently evolve by benefiting from additional features. That is what we call the rich snippets.
These rich snippets feed on data on the page in order to give more detailed information. For a page product, it can be the price or the average of web users feedbacks, for example.
Beware. Optimizing properly your "rich snippets" doesn't mean that you'll get the Google first position right away. However, it will help the search engine understand what you want to tell them, which is not insignificant considering the competition.