CreateDocument

CreateDocument[{cell1, cell2, ...}, opts___] _RemoteNotebook

creates a notebook in memory and populates it with cells, where celli can be:

• _ any expressions (automatically converted to the input cell)
• _String expression (automatically converted to text cells aka markdown)
• ExpressionCell[expr_, "Input"]
• ExpressionCell[expr_, "Output"]
• TextCell[expr_]
• TextCell[expr_, "Title"]
• TextCell[expr_, "Section"]
• TextCell[expr_, "Subsection"]
• CellGroup[{cells...}] a group of cells (it will be flattened and it is kept only for compatibility with Mathematica)

The expression returns RemoteNotebook

For example:

CreateDocument[{"Here is a plot example", Plot[x, {x,0,1}]}, Visible->False]  // NotebookOpen 

Specify the cells style:

CreateDocument[{TextCell["S1", "Section"], ExpressionCell[x^2, "Input"]}];

Use Defer

CreateDocument[Defer[1 + 1]];

Options

Visible

By the default is True, that opens a notebook automatically after using provided "Window"

"Window"

For the case if Visible->True it will use CurrentWindow by the default to pop up a new window