Web Search Overview Crawling IR IR Tasks Ad-hoc search Find relevant documents for an arbitrary text query Filtering Identify relevant user profiles for a new document Classification Identify relevant labels for documents Question answering Give a specific answer to a question 12Web Search Overview & Crawling 12 IR Tasks ▪ Ad-hoc search ▪ Find relevant documents for an arbitrary text query ▪ Filtering ▪ Identify relevant user profiles for a new document ▪ Classification ▪ Identify relevant labels for documents ▪ Question answering ▪ Give a specific answer to a question IR