* Rhabditis(Caenorhabditis) drosophilae Kiontke, 1997

The 2020–21 FC Red Bull Salzburg season is the 88th season in club history. They are the defending League and Cup champions. The season covers the period from 1 July 2020 until 30 June 2021.

In mathematics, the inverse limit (also called the projective limit) is a construction that generalizes several other constructions that recur throughout various fields of mathematics, including products, pullbacks, intersections, and more. Inverse limits are taken of inverse systems, which are collections of morphisms (e.g. functions) indexed by a preordered set that satisfy the following compatibility condition: whenever A cone into this inverse system is pair consisting of an object called its vertex, and an -indexed family of morphisms all having domain and satisfying the compatibility condition: whenever . An inverse limit of this inverse system, if it exists, is a cone that also has an additional property known as the universal property of inverse limits. This universal property establishes a one-to-one correspondence between, on one hand, cones into the given inverse system and, on the other hand, a unique morphism into the limit object that is "compatible" with the limit's family of morphisms in that it satisfies for every index (and it is the only morphism with this property). Each individual element of may be thought of as "thread", which is an -indexed collection of elements that satisfies the (typically infinitely many) conditions stipulated by the given inverse system. If a limit of a system exists then in general, it might not be unique although it will always be unique up to a unique isomorphism that satisfies a certain compatibility condition. Inverse limits can be defined in any category, and they are a special case of the concept of a limit in category theory. Direct limits are considered the "dual" of inverse limits. Direct limits involve direct systems and cocones from that system, which are the "duals" of inverse systems and cones. Direct limits are cocones that also have the universal property of direct limits, which establishes a one-to-one correspondence between cocones from the direct system and unique morphisms from (rather than into) the direct limit's vertex satisfying a certain compatibility condition. Although there is a one-to-one correspondence between inverse systems and direct systems, the nature of inverse limits typically differs drastically from that of direct limits.