This document discusses issues, opportunities, and challenges related to big data. It provides an overview of big data characteristics like volume, variety, velocity, and veracity. It also describes Hadoop and HDFS for distributed storage and processing of big data. The document outlines issues in big data like storage, management, and processing challenges due to scale. Opportunities in big data analytics are also presented. Finally, challenges like heterogeneity, scale, timeliness, and ownership are discussed along with approaches like Hadoop, Spark, NoSQL databases, and Presto for tackling big data problems.