Nice landing page. If you Google "summarizer", you will find dozens of similar services for free. The mechanism behind it is very simple. A couple a years ago I built one from scratch in about 2 hours, then I accidentally deleted it and rewrote it in 15 minutes. Here's how most of them work:
1. Split the text into words
2. Rank each word based on how many times it appears in the text. For example, a word that appears 10 times gets 10 points, and so on.
3. Rank sentences based on the sum of the scores of each word inside them.
4. Return the top N sentences by score (N is up to the user), in the order in which they appear in the text.
For extra fancyness, exclude the most common articles and prepositions and give 2 points to proper nouns.
1. Split the text into words
2. Rank each word based on how many times it appears in the text. For example, a word that appears 10 times gets 10 points, and so on.
3. Rank sentences based on the sum of the scores of each word inside them.
4. Return the top N sentences by score (N is up to the user), in the order in which they appear in the text.
For extra fancyness, exclude the most common articles and prepositions and give 2 points to proper nouns.
Works surprisingly well.