Video narration
How would you measure the spacing between two neighboring rivets in a row? Think about a row of shirt buttons: you measure from the centre of one button to the centre of the next. That tells you their true repeated spacing, even though the visible gap is smaller. Use that same idea for rivets. In engineering, pitch is the centre-to-centre distance between two consecutive rivets in the same row. Start at the centre of one rivet and measure straight to the centre of the next. That is the key: pitch is not the clear space from one rivet edge to the next. That edge-to-edge gap is a different measurement. So, what is the spacing between neighboring rivets? It is the pitch: the centre-to-centre distance between two consecutive rivets in a row, just like measuring from one button's centre to the next.