The Helvetica Black is bolder than the bold version of the Helvetica Condensed i.e. the Helvetica Condensed Bold. In the Helvetica Condensed Black Oblique the characters are slanted towards the right from the top. This plus the fact that the typeface is very bold gives a lot of character to the otherwise neutral Helvetica Condensed.
Helvetica is a very popular sans serif typeface that is adapted to different languages including Hindi, Chinese, Japanese etc. All the European languages use this font extensively. And the Condensed Black Oblique version of the Helvetica is used when some items in a text need to be highlighted.
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