As surfing the internet is a very common practice nowadays, obtaining information about anything is simply one click away. However, the information we get in response may not always be precisely what we want. Then we hover around the paragraph under every link so as to understand what the page is really about. These paragraphs are just summaries of the main article. There is an unlimited number of articles, webpages, news, blogs, researches and other data on the internet, and it surely is impossible to manually summarize each article. And every minute of every day, many more new information is uploaded on the internet. One of the popular examples is to make a concise summary of lengthy news articles, but there exists many more instances of such which may be useful on a daily basis.
Search engines such as Yahoo, Google, and Bing make use of tools for automatic text summarizing for all lengthy documents. A summarizer is basically an algorithm which selects the most important sentences from a text document, and presents them in a structured and readable format but with reduced texts.
Tools for automatic text summarization employ two major approaches, which are the extractive and abstractive methods.
The scope of summarization of text is classified according to its input kind, such as a multiple or single document, purpose such as general, domain detailed, query-based, or means of output (abstractive or extractive).
Extractive method of text summarization picks sentences and phrases from the basic source document so as to create the summary. It entails different techniques from deciding on how relevant a phrase is in comparison to the source’s meaning.
Abstractive method of text summarization produces completely new sentences and phrases to derive the source document’s meaning. It is more challenging and its results are more realistic since it is eventually used by humans. This method selects and compresses source contents, and yet may consist of words absent in the source document.
Extraction method of summarization is more widely used because of its availability and easier approach. However, abstractive method is regarded as offering more universal solutions to the problem of abstraction.