web2c: TeX extensions
5.7 Extended TeX engines
========================
The base TeX program has been extended in many ways. Here's a partial
list.
e-TeX
Adds many new primitives, including right-to-left typesetting and
more registers. Now frozen. More info:
<https://ctan.org/pkg/etex>.
Aleph
This adds Unicode support, right-to-left typesetting, and more.
Omega was the original program. Aleph is an updated version with a
variety of bug fixes, and includes e-TeX. Aleph is not actively
maintained. More info: <https://ctan.org/pkg/aleph>,
<https://ctan.org/pkg/omega>.
pdfTeX
Can produce PDF as well as DVI files. It also incorporates the
e-TeX extensions, new primitives for hypertext and
micro-typography, reading/writing from pipes, and much more. In
TeX Live, the command 'etex' invokes pdfTeX to make all these
additions available with DVI output. Home page:
<http://pdftex.org>.
LuaTeX
Embeds the Lua programming language (<http://lua.org>) and opens up
the TeX typesetting engine to control from Lua, starting from the
pdfTeX capabilities as a base. Also natively supports UTF-8 input,
the OpenType and TrueType font formats, and use of system fonts.
Home page: <http://luatex.org>.
XeTeX
Combines support for Unicode input, the OpenType and TrueType font
formats, and use of system fonts with the capabilities of pdfTeX,
with the exception of the font expansion part of micro-typography.
Home page: <https://tug.org/xetex>.
pTeX
upTeX
With additional support for Japanese; pTeX was the original engine,
and upTeX has native Unicode support and thus is more useful for
Chinese and Korean. More info: <https://ctan.org/pkg/ptex>,
<https://ctan.org/pkg/uptex>.
epTeX
eupTeX
Further extends pTeX and upTeX with the e-TeX extensions. More
info: <https://ctan.org/pkg/eptex>, <https://ctan.org/pkg/euptex>.
Info Catalog
web2c: IPC and TeX
web2c: TeX