I am doing project in Quandles . And I am reading Thesis by David joyce An Algebraic Approach to Symmetry with Applications to Knot Theory . In its Section 4.5 Knot quandles page number 46 there is a line " when a loop in X-K links once with K " , I am not getting what it means . And after that knot quandle is defined as nooses linking once with K upto homotopy which is also not clear to me . I have not done course in Algebraic topology and knot theory but I have read fundamental groups myself . If possible please explain through figure.
Any type of help will be appreciated.