A graph drawing in the plane is called an almost embedding if the images of any two non-adjacent simplices (i.e. vertices or edges) are disjoint. Almost embeddings (more precisely, their higher-dimensional analogues) naturally appear in combinatorial geometry, in topological combinatorics, and in studies of embeddings. We prove some relations between the invariants. We demonstrate the connection of some of these relations to homology of the deleted product of a graph. We construct almost embeddings realizing some values of these invariants. We present some ideas of algebraic and geometric topology in a language accessible to non-topologists (in particular, to students). All the necessary definitions are recalled. However elementary, this paper is motivated by frontline of research; there are some conjectures and open problems.

翻译：若任意两个非相邻单形（即顶点或边）的像互不相交，则称平面中的图绘制为几乎嵌入。几乎嵌入（更准确地说，其高维类比）自然出现在组合几何学、拓扑组合学以及嵌入研究中。我们证明了这些不变量之间的一些关系。我们展示了其中部分关系与图删除积的同调之间的联系。我们构造了实现这些不变量某些值的几乎嵌入。我们以非拓扑学家（特别是学生）可理解的语言呈现了代数拓扑和几何拓扑的一些思想。所有必要定义均已回顾。尽管内容基础，本文受到研究前沿的启发；文中包含一些猜想和未解决问题。