This paper is expository and is accessible to students. We define simple invariants of knots or links (linking number, Arf-Casson invariants and Alexander-Conway polynomials) motivated by interesting results whose statements are accessible to a non-specialist or a student. The simplest invariants naturally appear in an attempt to unknot a knot or unlink a link. Then we present certain `skein' recursive relations for the simplest invariants, which allow to introduce stronger invariants. We state the Vassiliev-Kontsevich theorem in a way convenient for calculating the invariants themselves, not only the dimension of the space of the invariants. No prerequisites are required; we give rigorous definitions of the main notions in a way not obstructing intuitive understanding.

中文翻译：

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基本结和链接理论的用户指南

这篇论文是说明性的，可供学生阅读。我们定义了节点或链接的简单不变量（链接数、Arf-Casson 不变量和 Alexander-Conway 多项式），其动机是由非专家或学生可以访问的有趣结果驱动。最简单的不变量自然会出现在试图解开结或断开链接的尝试中。然后我们为最简单的不变量提供某些“skein”递归关系，这允许引入更强的不变量。我们以一种便于计算不变量本身的方式陈述 Vassiliev-Kontsevich 定理，而不仅仅是计算不变量空间的维数。不需要先决条件；我们以不妨碍直觉理解的方式给出了主要概念的严格定义。