Always label your charts

Without labels, your chart is incomplete. McKinney’s rule of thumb: set_xlabelset_xlabel names the x-axis, set_titleset_title names the whole subplot, and both can be set together with one call to ax.set(title=..., xlabel=..., ylabel=...)ax.set(title=..., xlabel=..., ylabel=...) — handy once you’re labelling many subplots at once.

  flowchart LR
  A["Raw plot"] --> B["ax.set_xlabel('Day')"]
  B --> C["ax.set_ylabel('Orders')"]
  C --> D["ax.set_title('what changed, not just the chart type')"]
  D --> E["Reader understands the chart without extra context"]

import matplotlib.pyplot as plt
 
x = [1, 2, 3, 4]
y = [100, 120, 90, 150]
 
plt.figure(figsize=(7, 4))
plt.plot(x, y, marker="o")
plt.title("Daily orders")
plt.xlabel("Day")
plt.ylabel("Orders")
plt.tight_layout()
plt.show()

import matplotlib.pyplot as plt
 
x = [1, 2, 3, 4]
y = [100, 120, 90, 150]
 
plt.figure(figsize=(7, 4))
plt.plot(x, y, marker="o")
plt.title("Daily orders")
plt.xlabel("Day")
plt.ylabel("Orders")
plt.tight_layout()
plt.show()

Include units

Examples:

• Revenue (₹)
• Duration (seconds)
• Conversion rate (%)

Tip

A good title explains the question, not just the chart type.

Bad: “Line chart”

Better: “Daily orders increased after campaign launch”

Next

Continue to Legends and Colors to distinguish multiple series clearly.

🧪 Try It Yourself

Exercise 1 – Title and axis labels together

Exercise 2 – Custom tick labels

Exercise 3 – Rotate long labels