Complex sentence: In some texts these symbols are simply shown in bold type: blackboard bold in fact originated from the attempt to write bold letters on blackboards in a way that clearly differentiated them from non-bold letters i.e. by using the edge rather than point of the chalk.
Split into simpler sentences: In some texts these symbols are simply shown in bold type. Blackboard bold in fact originated from the attempt to write bold letters on blackboards in a way that clearly differentiated them from non-bold letters i.e. by using the edge rather than point of the chalk.