Section 1 - Instruction

Often, dates in a dataset are stored as plain text, like '2023-10-26'. While this looks like a date to us, the computer just sees it as a string of characters. This limits what we can do with it.

Engagement Message

What kind of date-related questions would be hard to answer if dates were just text?

Section 2 - Instruction

When dates are stored as text, sorting may appear to work but is unreliable. It only matches true chronological order if every value uses the same zero-padded ISO format (YYYY-MM-DD). Real datasets often mix formats or lack padding, which can misorder values (e.g., 2023-2-10 may sort after 2023-11-02). Converting to datetime ensures reliable sorting and enables date arithmetic.

Engagement Message

With me so far?

Section 3 - Instruction

The solution is to convert these strings into a special "datetime" object. This is a data type that Pandas understands as an actual date and time, not just text. This unlocks powerful time-based analysis capabilities.

Engagement Message

What types of time-based analysis become possible with proper datetime objects?

Section 4 - Instruction

Pandas has a powerful function for this: pd.to_datetime(). You apply it to a column of date strings, and it intelligently converts them into proper datetime objects. For example: df['date_col'] = pd.to_datetime(df['date_col']).

Engagement Message

Why is it helpful that this function can often guess the date format automatically?

Section 5 - Instruction
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