If you are reading from a Technique Book it is worth knowing that a step starts when the feet are side by side and finishes when the moving foot either closes to the standing foot or it under the body. If the book says do something at the end of step one you can take it that is what it means.

"If you are reading from a Technique Book it is worth knowing that a step starts when the feet are side by side and finishes when the moving foot either closes to the standing foot or it under the body. If the book says do something at the end of step one you can take it that is what it means."

That's the rule for passing steps, except for the "under the body" part which isn't in the book.

For closing steps, the previous step ends and the closing step begins when the foot is halfway closed.

Paying attention to this difference is quite important if you want to literally interpret the technique book's comments on a dance like waltz which uses a mixture of passing and closing steps.