In the typography is baseline (also baseline ) the status line of uppercase and lowercase letters . The space above the writing or base line is intended for middle heights, ascenders and accents, the space below for the descenders.
In some countries there are mandatory specifications or standards for the baseline. In many type foundries, however, the x is placed exactly in the middle of the cone , so that the same space remains for ascenders and descenders. According to this principle, for example, all fonts of Monotype Corporation produced. The phototypesetting requires identical relations with all font sizes , as used here for all or more degrees of the same negative, the baseline can be accurately determined at any rate must be prior to the drawing.
In Germany, the so-called normal font line applies, which provides a different relation of the descenders to the middle heights and ascenders for each degree.
For a long time, the products of type foundries were not compatible with one another. All had their own standard and only products of their own manufacture were interchangeable with one another. The main problem was that two different typefaces from different manufacturers could have the same cone height (for example 24 points ), but did not have to have the same baseline when they were next to each other. This was difficult to handle in the practice of typesetting , which is why in Germany in 1905, among other things, at the suggestion of the type foundry Genzsch & Heyse, AG , an agreement was made on the so-called "German normal script".
For a certain font size, the vertical space requirement of the ascenders and descenders was determined as a percentage of the height of the cone. So the baseline was precisely defined. Many existing fonts had to be redrawn, however, because their original designs could not be reconciled with the space required after the standardization.
The cone height was also important for interchangeability . This is the height of the entire font (i.e. not the side on which the typeface is on, but the height of the upright font), measured at 20 ° C. The Deutsche Höhe (also called Leipziger Höhe) was the standardized font height of 66 points, in contrast to the wider normal height of 62 2/3 points.
The normal font line leaves the descender a space of 20 to 27 percent of the cone for the various font sizes, and the descenders must therefore be changed several times when producing the font. Another disadvantage of the normal font line is that in some degrees there is not enough space for the descenders and the lower curve of the g in particular appears cramped and stunted.
It is good if enough space is planned for the accents above the capital letters when drawing . If you look at some of the older fonts, you can see that the accents were made makeshift later. However , the accents are very important for the legibility of some languages (e.g. French , Czech , Hungarian , Polish ). Experience has shown that the accents should be around eight percent of the height of the overall cone. Since this problem only occurs with uppercase letters, the ascenders of the lowercase letters can be kept larger than the basic form of the uppercase letters; you can let the ascenders of the b, d, f, h, k, 1 and ß protrude into the space provided for the accents of the capital letters.