> For the complete documentation index, see [llms.txt](https://vikram-bajaj.gitbook.io/cs-gy-6313-information-visualization/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://vikram-bajaj.gitbook.io/cs-gy-6313-information-visualization/data-abstraction-and-transformation/data-profiling.md).

# Data Profiling

Data Profiling is the process of familiarizing oneself with the data.

Data Familiarization/Profiling is needed because:

* Data may come from multiple sources
* The meaning of the data/attributes may not be evident
* Sufficient effort and interaction with subject matter experts may be needed to understand the meaning of the data/attributes in the data

It is also important to ensure data quality before attempting to create a visualization. Some quality issues include erroneous values, values with wrong types, missing values etc. The process of transforming poor quality data into usable data is called **data wrangling**.