Jupyter Notebook Interface Introduction | Beginner's Tutorial

After successfully launching Jupyter Notebook, you will encounter two core interfaces:

• File Browser Interface
• Notebook Editing Interface

1. File Browser Interface

When you launch Jupyter, this is the management interface you see, similar to a file explorer with backend control features:

• Working Directory: This displays the folder where you launched Jupyter.
• Note the icon color: If the notebook icon is green, it means the document's kernel is running in the background, occupying CPU and memory; gray means the file is saved but not active.

Clicking the Running tab allows you to view all running Notebooks at a glance:

The New button is used to create a new notebook, usually selecting the first option Python 3.

If you downloaded someone else's .ipynb tutorial, use Upload to import it into the current directory.

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Notebook Editing Interface

After clicking to create a new file, you enter this interface, which is the Notebook editing interface.

1. File Renaming: Click the title next to the Jupyter Logo in the upper left corner (such as Untitled), and a rename dialog will pop up.

2. Save and Revert: Under the File menu, Revert Notebook to Checkpoint, Jupyter will create checkpoints. If you mess up your code, you can roll back to a previous state at any time.

Toolbar

The three most core actions in the toolbar:

• Insert (+): "Add a line" below the current cell.
• Control (scissors, copy, paste): Used to adjust the order of code blocks.
• Run logic: Run ( ▶ ) executes the current block; Interrupt ( ■ ) forcibly stops code with errors; Restart ( ↻ ) is equivalent to powering off and restarting the brain, clearing all previously run variables.

Cell

Cells are the soul of Jupyter, and they have two identities:

• Code mode: There is In on the left. The number is very important: it represents the execution order of the code.
• For example: if you define a = 10 in the 1st cell, then writing print(a) in the 4th cell will also work wonders, as long as your execution order is correct.

• Markdown mode: There is no In on the left. After writing, run it, and it will instantly transform from raw text into a beautiful document with headings, bold text, and even mathematical formulas.

On the right side of the cell, you can perform operations such as moving the cell position:

Upper Right Corner: Kernel Status Indicator

• Hollow circle ( ○ ): The brain is idle, waiting for commands.
• Solid black circle ( ● ): The brain is running at full speed (calculating).
• No Kernel / Python 3: If it shows No Kernel, click it to reconnect, otherwise the code cannot run.