Areas inside Blender which are commonly mistakenly called windows, are parts of the user interface which contain specific editors such as the 3D viewport, UV editor, Outliner and so on.
These areas can be moved and adjusted in size to the users liking to create a workspace that suits them

Blender Areas can be identified by the editor button in the top left corner of each area. Once you press this button you can choose another editor to go in its place.

Resizing an area #
To resize an area inside of blender, you move your cursor over to the border of the area. Once you are there a cursor will appear indicating that this can be either slid up and down, or left and right depending on the direction this border is facing.
You can then click and drag this window into the position you require


Splitting And Joining #
Splitting and Joining an area can be done in two ways. The first way is to move the mouse into the very corner of any area you like. A crosshairs will appear in place of your computer mouse cursor, then if you click and drag you’ll have the option to split the window or if you keep holding you can drag it in the other direction to join it to a previously made area

Not only that, the user can right click on the border of an area and be given the option the split or join the area, and in which direction
Here we can see the options to split vertically and horizontally and also to join or swap the areas

If the user chooses to split, the user is then shows an indicator line that lets them choose where the split should happen.

If the user decides to join areas a further indicator mouse cursor will appear, and the chosen areas will get a new border indicating where the join areas will happen. The user can press the left mouse button to confirm their action.

Duplicate Area Into New Window #
Some editors have a seperate menu called View. This menu will sometimes have an additional option called Duplicate area into new window. View>Area>Duplicate area into new window
This will take the current area and make a brand new floating window which can be moved to another monitor or another position on the current monitor. Now the user has two windows.
This new window, like blenders usual interface, will allow users to change it to another editor or workspace layout to match their needs. Having two windows can be incredibly helpful in a lot of cases. With two windows, one can be for uv editing and the other can be for 3D modeling for example.
Toggle Fullscreen area #
If the user moves their cursor over to a chosen area, they can press CTRL + ALT + Spacebar which will expand the current area so it fills the whole window. This is a great way to focus on the work you are doing in one area, before exiting this view and continuing with the usual workspace layout.
Common Questions #
What are areas in Blender? #
In short, areas in Blender are spaces which contain different editors to get work done. One area may have a 3D viewport while another may have a properties panel serving different a operation. Each area in Blender can be adjusted and resized to create a workspace the user is comfortable with.
How do you add an area in Blender? #
You can add an area inside of Blender by going to the border of any area and right clicking and selecting split area. You can split this area into two and choose what this area should be by selecting the editor selection button in the top left corner.
You can also move your mouse to the very corner of any area until a crosshair cursor appears, you can then drag out a new area.
What is a Blender region? #
A region in Blender is is a way to describe specific parts of an editor which can include controls, widgets, tabs and panels. So in terms of areas, you may create an area and make this area into a 3D viewport editor. The 3D viewport will have its own regions to select/modify/change objects in the 3D vewport.
What are the default areas in Blender? #
The default areas in Blender change depending on the default workspace chosen by the user, but in general the 3D viewport, the Outliner, the Properties and the Timeline editors are usually the defaults placed into the areas in Blender.
How do I get area options in Blender? #
Some editors allow you to have a few options relating to the area. You can find these by going to View>Areas and selecting the option you want.
How do you split windows in Blender? #
Splitting a window in Blender, which refers to the entire user interface, can be done by going to Window in the Topbar and selecting New Window, or New Main Window. The user is then free to adjust the areas to their liking.