YogFont is the name of the exclusive font that members of the Yogscast usually use. Originally, it was created by Duncan Jones, but a new version has been made by, presumably, Teutron and VeteranHarry. All members of the Yogscast have used this font at least once. Most of them use this font for everything they can use it for. For example, YouTube video thumbnails.
The Current FontEdit
The font that the Yogscast use from the late period of 2013 to current times is somewhat different from the original YogFont. This font is loosely based on the font, Otaku Rant (bold), but the Conquest channel, uses Otaku Rant (light) because its for kids and is light entertainment. This current YogFont is most likely made by VeteranHarry and it is not publicly available. The change was made in late November/early December 2013. As of April 2016, during the OneShot Orcs Must Die! Unchained episode, it was revealed that the name of this font is Almighty Prunes, so that it appears first or very early on the font list.
The Original FontEdit
YogFont was the official Yogscast font that all members of the Yogscast used. Many people assumed that it was the font Badaboom BB, the previous font used by the Yogscast. However it was not the font itself, it was Badaboom modified by Duncan. It was modified possibly to avoid copyright issues. Typically Lewis doesn't give out the font but has done so in the past on a Reddit thread. You can download the font here. The first release of the font, according to the font's file, was May 12, 2011.
Badaboom BB Edit
This was the first font used by the Yogscast. The original YogFont was based on this font.