Big data refers to large sets of structured, unstructured and semi-structured data which has the potential to be mined and analyzed to determine patterns and trends .
Big data is characterized by the following:
1. Volume: Large amount of data from various sources.
2. Velocity: Data is being generated at high speed and should be dealt with in near real time.
3. Variety: Data can be in different formats.
4. Variability: Data can be highly inconsistent.
5. Complexity: Since data comes from multiple sources, complexity of linking, matching and cleaning data increases.