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The paper comprises a graphical calculus which is designed to deal with the Coxeter-Dynkin series of type E and some generalizations. Temperley-Lieb algebras of type E are defined as quotients of Hecke algebras and the module structure of the algebra associated to E 6 is determined. The graphical calculus is a refinement of the calculus for the ordinary Temperley-Lieb algebra: a planar strip is decomposed by the arcs of a diagram into domains and the domains are used to incorporate additional information into the figure.

Let W be a finite Coxeter group. We define its Hecke-group algebra by gluing together appropriately its group algebra and its 0-Hecke algebra. We describe in detail this algebra (dimension, several bases, conjectural presentation, combinatorial construction of simple and indecomposable projective modules, Cartan map) and give several alternative equivalent definitions (as symmetry preserving operator algebra, as poset algebra, as commutant algebra, ...). In type A, the Hecke-group algebra can be described as the algebra generated simultaneously by the elementary transpositions and the elementary sorting operators acting on permutations. It turns out to be closely related to the monoid algebras of respectively nondecreasing functions and nondecreasing parking functions, the representation theory of which we describe as well. This defines three towers of algebras, and we give explicitly the Grothendieck algebras and coalgebras given respectively by their induction products and their restriction coproducts. This yields some new interpretations of the classical bases of quasi-symmetric and noncommutative symmetric functions as well as some new bases., v2: 30 pages, 2 figures, extended proof of Prop. 3.25, update of citations, typo and grammar fixes v3: final version: typos and encoding fixes