Answer
I think the Wikipedia kerning article essentially covers it, but the bulk of the article is about adding kerning information to a font during its design, or applications automatically using this built-in information to improve composition of a font’s characters — rather than the a fine-tuning a designer might do on a particularly problematic pair of characters in a headline.
As an example, say the revolutionary new product, the
iVone
was launched; that combination of italic/oblique and roman characters would probably not have been foreseen by the font designer, and so would require special treatment to avoid the dot of the i from colliding with the V.
Letter-letter, or letter-punctuation combinations that are only used in some languages are other situations that might require custom kerning by a designer.
Also to note, fonts contain widely varying amounts of kerning information – this is one of the key differentiators between amateur and professionally produced fonts, or even between different versions of the same font.
Attribution
Source : Link , Question Author : John , Answer Author : e100
