Limbo is a ProgrammingLanguage intended for applications running distributed systems on small computers. It supports ModularProgramming, strong type checking at compile- and run-time, interprocess communication over typed channels, automatic GarbageCollection, and simple abstract data types. It is designed for safe execution even on small machines without hardware memory protection.
The same people that were so critical of NiklausWirth are now advocating/borrowing from Wirth's languages significantly. I detect hypocrisy and irony here. This looks like some famous C programmers kidnapped Niklaus, took him to some cabin in the wilderness, and then robbed and stole from him his Modulas. After this kidnapping, they left him tied up and humiliated there for several years, where he could not absorb any fame out in the styx. Brushing it under the table, few credits given to Wirth's name, someone mentions "that kind of looks like Modula?" on a C2 wiki and the Wikipedia. Hmph.
The tone of the above statement seems a bit silly given that Wirth's influence on Plan 9 and Inferno via Oberon is known, and documented in the... documentation... of the same. There is some discussion of this over in [OberonOperatingSystem]
Alef was an ancestor of Limbo: http://doc.cat-v.org/plan_9/2nd_edition/papers/alef/RobPike's Squeak is an even older ancestor: http://doc.cat-v.org/bell_labs/squeak/
And Google's Go contains many ideas based on Limbo.