What is a Zero-Based Budget?

Simply put, monthly income - monthly expenses = $0. If you have excess remaining after expenses, save it. If your expenses outpace your income, you need to refine your budget. So easily said, right?!
Well, truth be told, most American families don't have a defined, written budget and for this reason, they live paycheck-to-paycheck. Even if they do have a budget, unfortunately, most folks lack the discipline to stick to it.
What are the ranges of acceptable spending in a responsible budget? According to Dave Ramsey, they look like this:

• Health 5-10%
• Recreation/Entertainment 5-10%
• Utilities 5-10%
• Food 10-15%
• Charity 10-15%
• Savings 10-15%
• Personal 10-15%
• Transportation 10-15%
• Insurance 10-25% - MASSIVE RANGE HERE, due to one's various driving & health conditions
• Housing 25-35% - 35 is TOO HIGH in my opinion but tell that to peeps in SF or NYC