The Shiki Highlighter plugin enhances syntax highlighting in Obsidian by integrating Shiki through Expressive Code, supporting over 100 programming languages. It provides consistent highlighting in reading, live preview, and edit modes, offering features such as line numbers, customizable themes, and various code block configurations. Users can highlight specific lines, add headers, and enable diff highlighting to track code changes. The plugin also supports inline highlighting and allows custom JSON themes compatible with VS Code. With its robust capabilities, this plugin is ideal for those seeking improved visual clarity and customization in their code notes.