page_title: Blackboard bold
hierarchical_section_title: Blackboard bold
context_page_description: Blackboard bold is a typeface style that is often used for certain symbols in mathematical texts, in which certain lines of the symbol are doubled. The symbols usually denote number sets. One way of producing blackboard bold is to double-strike a character with a small offset on a typewriter. Thus they are also referred to as double struck.
  In typography, such a font with characters that are not solid is called an "inline", "shaded" or "tooled" font.
context_section_description: Blackboard bold is a typeface style that is often used for certain symbols in mathematical texts, in which certain lines of the symbol (usually vertical or near-vertical lines) are doubled. The symbols usually denote number sets. One way of producing blackboard bold is to double-strike a character with a small offset on a typewriter. Thus they are also referred to as double struck.
  In typography, such a font with characters that are not solid is called an "inline", "shaded" or "tooled" font.
caption: An example of blackboard bold letters