Write & punctuate measurements correctly

What Comes First? Width or Height?⁠ The design industry standard is width by height (width x height). Meaning that when you write your measurements, you always start with the width. ⁠

Why is it important? When you give me instructions to create a 297 × 210 mm poster, I will design a poster that is wide, not tall. ⁠

All major graphic software use width by height in order to determine orientation. But is way more simple: the way we read (assuming you read English / Czech literature…) is from left to right, first, then down the length of the page. ⁠

Another example is TVs, they are 4 × 3 or 16 × 9 ratios, not 9 × 16. ⁠

We can also imagine a simple chart with X and Y axes! X comes before Y, doesn’t it?⁠⠀

*More typographic rules: ⁠
The denotation of metric units, either alone or joined with a prefix, always starts with a lower case letter – e.g. meter, milligram, watt.⁠
While using a symbol: Symbols never pluralize, Like 25kg.⁠
While writing in full: 25 kilograms⁠
Please note that there are always some exceptions.⁠