## Understanding `df.` in Python In Python, `df` is a **variable name** that refers to a **DataFrame** — a table-like structure provided by the `pandas` library. When we use `df.` in a command, we are instructing Python to operate on that specific dataset. ### Examples of `df.` Usage | Command | Meaning | |----------------------|-------------------------------------------------------------------------| | `df.head()` | Show the first 5 rows of the DataFrame | | `df["tip"]` | Access the `tip` column | | `df.tip` | Another way to access the `tip` column (only works if the name has no spaces) | | `df.describe()` | Display summary statistics (mean, std, min, max, etc.) | | `df.groupby("sex")` | Group the data by the `sex` column for analysis | ### Summary - `df` is the variable holding your table of data. - `.` allows you to apply methods or access columns from that DataFrame. - It’s the standard way to work with data in pandas.