Text summarization involves generating a summary of a document using computer programs. It is needed because the amount of textual information is growing rapidly, making it difficult for users to read everything. There are two main types of summarization: extraction, which selects important sentences from the original text, and abstraction, which generates a summary using semantic analysis. The document describes and compares two summarization algorithms - reduction and intersection - and provides screenshots of a program implementing the algorithms. It concludes that reduction creates better summaries but is slower, while intersection works well on some documents but often generates very short summaries.