CSS Grid is a robust and flexible web layout system that represents a paradigm shift from previous CSS methods, offering precise design control while simplifying code.

The main features and best practices for this tool include:

• Use Names Instead of Numbers: It is recommended to name grid areas (e.g., sidebar, main) rather than referring to columns and rows by numbers. This significantly improves readability and makes the code future-proof, as it allows you to swap visual orders without touching the underlying content.

• The Fractional Unit (fr): This unit allows you to distribute available space based on fractions. It delegates complex arithmetic to the browser's layout engine, preventing manual math errors and issues associated with percentages.

• Reducing Code "Noise": Rather than literally replicating a designer's 14-column system, it is better to only define the columns actually being used. This makes the code less noisy and more reflective of its actual use.

• Independent Nested Grids: Since CSS Grid does not have a concept of inheritance, you should create micro-grids within content elements for local alignments. This keeps elements simple and internally consistent without needing to know about the top-level grid.

• Separation of Content and Presentation: The system allows for cleaner, flatter HTML because you do not need to add unnecessary "wrapper" divs just to make the styling behave correctly.

• High Skill Floor: Effective use requires learning approximately 18 new properties and internalizing a completely new layout paradigm, which can be difficult initially but offers great rewards once mastered.