The video starts at 0:20 after the introduction provided by Blender Academy on YouTube.
The default startup file in Blender displays a cube primitive within the Perspective Viewport, a large viewport window with a grid floor, represented by these grey lines, as well as green and red lines that intersect the cube.
The cube is highlighted with an orange line around it, signaling that this object is the active selected object. The orange dot in the center of the cube is its point of origin. In other words, it’s the cube’s origin where the origin is set to geometry. The cube’s current location in 3D space is XYZ = 0 (zero).
The circle around the orange dot inside the cube is Blender’s 3D Cursor. The cursor also holds its location at XYZ = 0 (zero).
To put it simply, what I mean by XYZ is that these are the main navigation lines in 3D space, where you can see that the red X-line and the green Y-line intersect each other. That point itself is called the origo or origin.
In 3D language, we usually refer to these as the X-axis, Y-axis, and Z-axis. Others will refer to these as the red, blue, and green axes.
The black triangular figure looking at the cube is the visual representation in Blender of a camera object. The other one is a light object or light source. It represents the light source from something such as a lamp that affects the surrounding surfaces, including the cube.
Navigating around in 3D space like an astronaut
- Zooming in/out (mouse) – Use the scroll wheel to scroll forward or backward.
- Orbit (mouse) – Hold down the scroll wheel/middle mouse button while moving the mouse.
- Pan (mouse) – Hold down the scroll wheel/middle mouse button and the SHIFT key on the keyboard while moving the mouse.
If you lose track of your cube or selected object in 3D space, the hotkey to get you safely back is * , * (comma) on your NumPad or the HOME key on your keyboard. Alternatively, you can click “View” next to “Object Mode” and select “Frame All” from the drop-down.
Orbiting the view can also be done by left-clicking inside the navigation gizmo in the top-right corner of the viewport (where you see the blue, red, and green axes) and holding down the left mouse button to orbit the view.
The button below that one allows you to zoom in and out. To zoom in and out, hover your cursor above the magnifying glass icon, left-click and hold to zoom in, and left-click and hold again to zoom out.
Hovering your cursor above the hand symbol by left-click and holding will pan the view.
To practice this, I highly recommend watching the rest of the video.