LaTex is a popular editor used by publishers
Texmaker : Free cross-platform LaTeX editor

Features

* an unicode editor to write your LaTeX source files (syntax highlighting, undo-redo, search-replace, ...)
* the principal LaTex tags can be inserted directly with the "LaTeX" and "Math" menus
* 370 mathematical symbols can be inserted in just one click
* wizards to generate code ('Quick document', 'Quick letter', tabular, tabbing and array environments)
* LaTeX-related programs can be launched via the "Tools" menu
* the standard Bibtex entry types can be inserted in the ".bib" file with the "Bibliography" menu
* a "structure view" of the document for easier navigation of a document (by clicking on an item in the "Structure" frame, you can jump directly to the corresponding part of your document
* extensive LaTeX documentation
* in the "Messages / Log File" frame, you can see information about processes and the logfile after a LaTeX compilation
* the "Next Latex Error" and "Previous Latex Error" commands let you reach the LaTeX errors detected in the log file
* by clicking on the number of a line in the log file, the cursor jumps to the corresponding line in the editor
* an integrated LaTeX to html conversion tool (for unix and macosx systems)

(see the user manual for more details)