The grid is visual music to the web. It provides rhythm, tempo and harmony within a page. The symphony of the grid provides a beautiful experience for a design.
Before I was into design, I grew up playing music. At a young age I took piano lessons, played drums and picked up a guitar. In all of this, I found patterns within music that can be transferred to design.
One of the key things I have learned about all things musical is that music theory allows you the ability to see an overall pattern in how things are written, played and composed. Once you know key parts of music theory, you can play along with most songs and pick up and learn any instrument (once you know the basics of how that instrument works).
In design, the grid maintains a musical rhythm and provides a consistent tempo to a page. It keeps things in sync regardless of the instruments you are choosing to play on your page or the genre in which your design takes place. Like music, design needs rhythm and a tempo to guide the visual experience and maintain a movement throughout.
Just as every symphony has a rhythm, a tempo, and instruments to texture the foundation of the piece, web design and the grid is the visual version of delivering content in the symphonic visual format.