In general the process of taking some convoluted internal data structure and generating a linear representation of it that can be used to reconstruct the internal data structures at a later time. This is the fundament underlying persistence and transfer of complex data over channels.
Examples on the wiki
Great that be doable, better that be done (where worries go).
TV But in various cases it should be so much simpler... Agreed, though. - RS: This page lists only the nontrivial cases. Other languages will have to worry about how to serialize an integer, a double, a list, an array... which Tcl all provides with built-in string reps, as specially simple case of serialization.
escargo 21 Feb 2004 - This could also be seen as an implementation of the Memento design pattern.