Logic and Semantics for Dummies (LSD) is a very informal weekly meeting for PhD students in the Computer Laboratory (other dummies may be admitted). Each week, a volunteer will research an unfamiliar topic and give an informal talk on his/her findings. The talks tend to be about the more theoretical and mathematical aspects of theoretical computer science, giving students a chance to learn some of the foundations of various research directions. Talks are supposed to be pitched at a very basic level.