doc edits for kernel-backed documents.

docs/source/user/documents_kernels.md

@@ -1,24 +1,25 @@
 
 ## Kernel backed documents
 
-In the Jupyter architecture, Kernels are separate processes started by the
-server that run your code in different programming languages. JupyterLab allows
-you to connect any open text file to a code console/kernel. With this, you can
-run code from the text file in the kernel interactively.
+In the Jupyter architecture, kernels are separate processes started by the
+server that run your code in different programming languages and environments.
+JupyterLab allows you to connect any open text file to a code console and
+kernel. This means you can easily run code from the text file in the kernel
+interactively.
 
-Right-click on the document and select “Create Console for Editor”: 
+Right-click on a document and select “Create Console for Editor”: 
 
 [animation]
 
-Once the code console is open, send a single line of code or a seletion of code
-to the code console by hitting `Shift Enter`:
+Once the code console is open, send a single line of code or select a block of
+code and send it to the code console by hitting `Shift Enter`:
 
 [animation]
 
-In a markdown document, `Shift Enter` will automatically detect if the cursor is
-within a code block, and run the entire block:
+In a Markdown document, `Shift Enter` will automatically detect if the cursor is
+within a code block, and run the entire block if there is no selection:
 
 [animation]
 
-It is important to emphasize that any text file (markdown, python, R, LaTeX,
-C++, etc.) can be connected to a code console/kernel in this manner.
+*Any* text file (Markdown, Python, R, LaTeX, C++, etc.) in a text file editor
+can be connected to a code console and kernel in this manner.