interface doc edits

docs/source/user/interface.md

@@ -1,92 +1,86 @@
+# The JupyterLab Interface
 
-# The Interface
-
-The JupyterLab provides the flexible building blocks for interactive,
+JupyterLab provides flexible building blocks for interactive,
 exploratory computing. While JupyterLab has many features found in traditional
-IDEs (Integrated Development Environments), it remains focused on interactive,
+integrated development environments (IDEs), it remains focused on interactive,
 exploratory computing.
 
-The JupyterLab Interface consists of a Menu Bar at the top, with a Left Panel
-and Dock Panel below. The Left Panel contains the File Browser, the Running
-List, the Command Palette, the Cell Tools Inspector and the Tabs List. The main
-work area for documents in JupyterLab is called the Dock Panel.
+The JupyterLab interface consists of a main work area containing tabs of
+documents and activities, a collapsible left sidebar, and a menu bar. The left sidebar
+contains a file browser, the list of running kernels and terminals, the command
+palette, the notebook cell tools inspector, and the tabs list.
 
 [screenshot]
 
 ## Menu Bar
 
-The Menu Bar at the top of JupyterLab has top-level menus that expose all of the
-actions available in JupyterLab, along with showing their keyboard shortcuts.
-The default menus are:
-
+The menu bar at the top of JupyterLab has top-level menus that expose actions
+available in JupyterLab with their keyboard shortcuts. The default menus are:
 
 - File: actions related to files and directories
 - Edit: actions related to editing documents and other activities
-- View: actions that reversibly alter the appearance of JupyterLab
+- View: actions that alter the appearance of JupyterLab
 - Run: actions for running code in different activities such as Notebooks and
   Code Consoles
-- Kernel: actions for managing Kernels, which are separately processes which run
+- Kernel: actions for managing kernels, which are separate processes for running
   code
-- Tabs: a list of the open documents and activities in the Dock Panel
-- Settings: common settings and an advanced Settings Editor
-- Help: a list of JupyterLab and Kernel related help links
+- Tabs: a list of the open documents and activities in the dock panel
+- Settings: common settings and an advanced settings editor
+- Help: a list of JupyterLab and kernel help links
 
-JupyterLab extensions can also create new top-level menus in the Menu Bar.
+JupyterLab extensions can also create new top-level menus in the menu bar.
 
-## Left Panel
+## Left Sidebar
 
-The Left Panel contains a number of commonly used panels, such as the File
-Browser, Running List, Command Palette and Tabs List:
+The left sidebar contains a number of commonly-used tabs, such as a file browser, a list of running kernels and terminals, the command palette, and a list of tabs in the main area:
 
 [screenshot]
 
-The Left Panel can be collapsed or expanded by clicking on the active tab:
+The left sidebar can be collapsed or expanded by clicking on the active sidebar tab:
 
 [animation]
 
-JupyterLab extensions can add additional panels to the Left Panel.
+JupyterLab extensions can add additional panels to the left sidebar.
 
-## Dock Panel
+## Main area
 
-The Dock Panel is the main work area in JupyterLab and allows you to arrange
-documents (notebooks, text files, etc.) and other activities (terminals, code
-consoles, etc.) into panels and tabs that can be resized or subdivided:
+The main work area in JupyterLab allows you to arrange documents (notebooks,
+text files, etc.) and other activities (terminals, code consoles, etc.) into
+panels of tabs that can be resized or subdivided:
 
 [animation]
 
-The Dock Panel has a single active document or activity that receives keyboard
-focus and whose tab is marked with a colored top border (blue by default):
+The main area has a single current activity. The tab for this activity is
+marked with a colored top border (blue by default).
 
 [screenshot]
 
-## Tabs and single-document view
+## Tabs and Single Document Mode
 
-The Tabs List gives you access to the open documents and activities in the Dock
-Panel:
+The Tabs panel in the left sidebar lists the open documents or activities in the
+main area:
 
 [screenshot]
 
-The same information is also available in the Tab Menu:
+The same information is also available in the Tabs Menu:
 
 [screenshot]
 
-It is often useful to focus your work on a single document, while not closing
-other documents. Single Document Mode toggles the view of the Dock Panel to show
-only a single document at a time:
+It is often useful to focus on a single document or activity without closing
+other tabs in the main area. Single Document Mode toggles the view of the main
+area to show only a single tab at a time:
 
 [animation]
 
-When you leave Single Document Mode, the original layout of the Dock Panel is
+When you leave Single Document Mode, the original layout of the main area is
 restored:
 
 [animation]
 
-
 ## Context Menus
 
-Many parts of JupyterLab, such as notebooks, text files, code consoles, Dock
-Panel tabs, etc. have context menus that can be accessed by right-clicking on
-the element:
+Many parts of JupyterLab, such as notebooks, text files, code consoles, and tabs
+have context menus that can be accessed by right-clicking on the element:
 
 [animation]