nofill – Preserve spaces and line breaks when setting text
The commands \fill and \nofill bracket text in which multiple spaces are not collapsed into a single space, and spaces at the start of line are preserved.
Maybe you are interested in the following packages as well.
- verbtim2: Verbatim listings in Plain TeX
- list: List ASCII text files
- astyped: Verbatim environment, with rather few escapes
- figplace: Floating figures in Plain TeX