Castillo TextEditor has Pascal/Delphi, C/C++, HTML, JavaScript, CSS, Perl, Visual Basic, SQL and Java syntax highlighting and has a unique feature of special interest for developers: PowerTag. PowerTag allows the user to set tags to the selected text, without converting the program in a specialized HTML editor. The user can totally configure the tags. Castillo TextEditor has an internal clipboard with support for up to 100 MB of text.

Castillo TextEditor environment provides multiple toolbars, for different editing/windowing options, such as Find Toolbar, Files Toolbar, Window List Toolbar, Bookmarks Toolbar and Internal Clipboard Toolbar

The program can also perform searches for a specified text in all the hard drive or an specific directory as easy as editing a document, you can even save the search results and reload them again later.

Castillo TextEditor allows you to edit multiple files using a convenient multi-document interface approach. The editor can load files of any size (limited by memory only).

The editor makes it easy to open recently used files and access already opened files through the Window List Toolbar. You can also open files by dragging-and-dropping them from the Explorer or the Files Toolbar.

Castillo TextEditor lets you have different settings for each document such as word wrap, auto indent, syntax highlighting language, etc, with a single click in the document toolbar.

The Internal Clipboard works similar to Windows clipboard, except that Windows clipboard can only handle 64 Kb of data while Castillo TextEditor's Internal Clipboard capacity is up to 100 mb of data.

The internal clipboard data is shown in the Internal Clipboard Toolbar, where you can edit the Internal Clipboard without having to paste in your document, editing it and cutting it again, just edit in this little window. This window also provides commands to copy Windows clipboard into Castillo TextEditor's Internal Clipboard and viceversa.

Also line numbers are shown in the leftmost part of the editor. They can be configured to show either the line numbers or paragraph numbers, by right-clicking in it and choosing Show Lines Numbers or Show Paragraph Numbers. This component also shows where bookmark are specified.