Docstring for ; Uses (#41952)

Author: annjc

base/docs/basedocs.jl

@@ -974,9 +974,19 @@ kw"..."
     ;
 
 `;` has a similar role in Julia as in many C-like languages, and is used to delimit the
-end of the previous statement. `;` is not necessary after new lines, but can be used to
+end of the previous statement.
+
+`;` is not necessary at the end of a line, but can be used to
 separate statements on a single line or to join statements into a single expression.
-`;` is also used to suppress output printing in the REPL and similar interfaces.
+
+Adding `;` at the end of a line in the REPL will suppress printing the result of that expression.
+
+In function declarations, and optionally in calls, `;` separates regular arguments from keywords.
+
+While constructing arrays, if the arguments inside the square brackets are separated by `;`
+then their contents are vertically concatenated together.
+
+In the standard REPL, typing `;` on an empty line will switch to shell mode.
 
 # Examples
 ```julia
@@ -993,6 +1003,19 @@ julia> foo();
 
 julia> bar()
 "Hello, Mars!"
+
+julia> function plot(x, y; style="solid", width=1, color="black")
+           ###
+       end
+
+julia> [1 2; 3 4]
+2×2 Matrix{Int64}:
+ 1  2
+ 3  4
+
+julia> ; # upon typing ;, the prompt changes (in place) to: shell>
+shell> echo hello
+hello
 ```
 """
 kw";"