No discussion about hacking would be complete without mentioning programming, which is what a true hacker does best. There is also a Language Comparison describing my views and takes on many languages, and what is best and worst of today's languages and features.

Here are my favorites:

Table of Contents

LISP
Oberon
COBOL
FORTH
C and C++
Smalltalk
Eiffel
SNOBOL and Icon
PL/1
Pascal
APL
BASIC
Postscript
HTML
CGI
Java
Multi-Language Resources

LISP

LISP is the oldest computer language in existance today except FORTRAN, and is widely used and implemented. It is an extensible language (LISPers call it incremental) - and probably going to be one of my favorites, next to Forth and Smalltalk. There are a lot of resources and implementations out there. And now, with the Common Lisp Object System (CLOS), it even has some object-oriented concepts within it! Recommended!

Implementations

Macintosh Common LISP - a commercial implementation sold to Digitool, Inc. by Apple Computer
LISP for Macintosh - is www.cambridge.apple.com gone?
Scheme - at MIT - home of MIT Scheme
Scheme: Revised report on the Algorithmic Language Scheme
The Scheme Underground Page
CMU Common Lisp
PowerLisp - a shareware LISP implementation for Macintosh
Dylan - a LISP variant pioneered by Apple Computer
Dylan World
Franz LISP for 386/BSD
XLISP and derivatives:
- XLISP v3.0 - the newest version of the original (not based on Common LISP)
- XLISP-STAT - a statistical version of XLISP
- XLISP-PLUS - created by Tom Almy (also creator of ForthCMP)
- Winterp - the OSF/Motif Widget INTERPreter (based on XLISP-PLUS)
CMU Lisp via FTP

Oberon

Oberon is a successor to Pascal by Niklaus Wirth (who seems to come up with a new language every decade or so). It is strongly typed and so on, and seems to have a lot in common with its predecessors, Pascal and Modula. I can't say how good it might be, but it doesn't seem to be around in the commercial and freeware markets in any significant strength - and you may find it's not available for your machine. I even found that one implementation of Oberon requires a Modula compiler to operate!

The Oberon Home Page
The Oberon Reference Site
Oberon System 3 from University of California-Irvine
Oberon Compilers
Oberon Microsystems

COBOL

COBOL, inspite of its reputation, should not be written off. The language is very widely used, has a long history, and continues to be upgraded every so many years, including the latest attempts at an ANSI Standard COBOL and even an ANSI Standard Object COBOL. I would probably never choose to write something in COBOL, but from a practical standpoint you can't go wrong learning COBOL.

Companies and Organizations

Flexus COBOL Page

COBOL650 Shareware COBOL Compiler

History

The Wit and Wisdom of Grace Hopper
Launching the Amazing Grace Hopper - info on both the USS Hopper and Grace Hopper
Grace Hopper: Mother of the Computer - from the Women's International Center
Grace Murray Hopper: A Legend in Her Own Time

Implementations

Free COBOL Starter Set CD - many free tools, some 90-day trials - from Fujitsu Software Corporation (sellers of the Fujitsu COBOL85 Compiler)
CobCy - Freeware COBOL Compiler - in development
Deskware COBOL Interpreter - shareware or freeware - in development
IBM COBOL Family

General Links and Resources

Forth

Forth was created by Charles Moore, in about 1973, because he wanted to be more productive. Unlike almost any other language today, Forth was not a research project or a committee design; it was created by one man to fulfill his needs. In my opinion, Forth is my favorite language and one of the best around today. It's too bad that it is not recognized and used by more people.

Companies and Organizations

Forth, Inc. - one of the primary FORTH solutions vendors
Mountain View Press - a top source for books and information, including public domain and shareware FORTH implementations
The Institute for Applied Forth Research - also publishers of The Journal of FORTH Application and Research
Laboratory Microsystems, Inc. - a FORTH vendor
FirmWorks - the Open Firmware source
Forth Interest Group (FIG)

Implementations

Frank Sergeant's Forth Page - creator of Pygmy
ForthCMP - created by Tom Almy (also creator of XLISP-PLUS)
Open Firmware - a Sun Sparc boot ROM based on FORTH
Neon - object-oriented Forth for the Apple Macintosh - a commercial FORTH released to the net as freeware:
- Mops - Neon reimplemented
- Yerk - Neon updated
F-PC - a top-quality Forth for MSDOS-based Intel PCs
Pocket Forth et al
Pocket Forth Official Site (Forth for Mac)

General Links and Resources

Introduction to Forth - What kind of language is it anyway?
Forth Research at the Institut fur Computersprachen
An Introduction to Forth
FORTH on the Web
Forth Online Resources Quick-Ref Card

C and C++

C and C++ are here to stay, and are becoming one of the most widely used computer languages (along with COBOL and FORTRAN), if they aren't already. These languages are nice, but I favor Smalltalk over C++ and Forth over C. However, C is a nice language to use, and aside from its edit-compile-run cycle, does have a lot going for it.

A Summary of Research in Object-Oriented Parallel Programming - including a significant list of C++ approaches to parallel processing - from the Ohio Supercomputer Center
C Programmer's Club - dedicated to teaching C, C++, and Postscript
C++ FAQ Lite - C++ Frequently Asked Questions in hypertext
Pacific Galaxy Developers Club - membership is free!
pC++ and Sage++ - versions of C++ designed for parallel processing
Ask the C++ Pro - from the people at inquiry.com
Jon's C++ Resources Directory
Introduction to Object-Oriented Programming Using C++
The C++ Virtual Library
C++ Annotations - an online introduction to C++ for C programmers
C++ Documentation - a nice list of links to check out
C Programming - an online manual
LCC-Win32 Unofficial Home Page - freeware 32-bit compiler for Win95/NT
C Programming - an extensive online tutorial (with a dozen or so mirrors! - including but not limited to:
Borland C++ Page - from Borland, Inc.
The International Obfuscated C Code Contest Home Page - and check out the IOCCC Archives
TTT System (Topic, Task, Test) - an experimental set of files and programs to teach C++ interactively
C/C++ Users Group (CUG) - an independent group sponsored by C/C++ Users Journal
Programmiertechniken: Parallel Programming in C++ - from Central Institute for Applied Mathematics (ZAM) at Forschungszentrum Julich (in Germany)
Visual C++ Resources on the Web
The Association of C and C++ Users
Internet Sites and Files of Interest to C++ Users
C++ Internet Resources - from EG3 - "electronic engineer's toolbox" - also downloadable
Windows C and C++ Resources - from The Programmer's Source
Programming in C - name is deceptively and limiting - this site covers much more than just "programming" in C

Smalltalk

Smalltalk, in my humble opinion, is the best and purest object-oriented language and system ever designed. Everything else tries to modify this pure form into something else - probably the best example of the worst case is C++. Smalltalk is one of my favorites, right up there with LISP and Forth - and like these languages, the actual language system is extensible. This language is a must!

Smalltalk/X
The Squeak Smalltalk Page at the UCSB Center for Research in Electronic Art Technology (CREATE)
Squeak - a freeware Smalltalk released by Apple Computer
IBM Smalltalk Tutorial
Jeff McAffer's Smalltalk Links
Runar Jordahl's Smalltalk Overview
6053 Links on Object Orientation (and growing!)
Smalltalk Archives - at UIUC - also available via FTP
Smalltalk Industry Council (STIC)
Room 333: Smalltalk Resources
ParcPlace-Digitalk, Inc.
ObjectShare, Inc. - where you can get Smalltalk Express for free!
Smalltalk for Macinosh

Eiffel

I don't know much about Eiffel, but it sounds like a good candidate for a freeware object-oriented system. I haven't discovered how close it holds to the OO ideology, and haven't tried it. However, I aim to consider it closely; I recommend you do too.

An Introduction to the Eiffel Language
Eiffel FAQ
Eiffel in Our Business
The Rainbow Project: Building Financial Software with Eiffel
The Eiffel Page - as well as an an outdated mirror
Eiffel: An Advanced Introduction
Eiffel Compilers: The SmallEiffel Archive
Geoff's Universal Eiffel Resource Locator (GUERL)
Eiffel: An Introduction, 1/e - a book
Why Your Next Project Should Use Eiffel by Bertrand Meyer
Formal Semantics and Interactive Environment for Parallel Object-Oriented Programming: Eiffel// (in plain english: Eiffel-// Home Page)
Eiffel Links listed by The World-Wide Catalog of Software Web Sites - a book
Interactive Software Engineering (ISE) - creators of Eiffel

PL/I

PL/I is a unique language; I would describe it as a systems language that resolved standards problems and user desires by incorporating it all into the language. This language has literally everything and was a chosen language for systems design in many places; however, C is much more concise, much faster, and less cumbersome. To me, PL/I can be classified as an oddity: study it just because it's there, it'll be fun!

PL/I Information from IBM:
UniPrise PL/I from UniPrise Systems, Inc.
PL/I Resources
Open PL/I from Liant

SNOBOL and Icon

SNOBOL and Icon are text processing languages from the same authors; Icon is the modern successor to SNOBOL. I have never tried Icon, but SNOBOL was fun and quite powerful in its text processing capabilities. I'm not sure what improvements Icon brings, but it might be worth examining if you have text processing needs.

Icon Home Page

Pascal

Pascal can be a very powerful language (as was evidenced by Borland's Turbo Pascal) but in most cases is limited to educational purposes. This is not really a problem or a mistake; Pascal was designed to teach programming. However, it has gone beyond that in many ways.

Ultimate Pascal
Pascal Programmer's Paradise
Turbo Pascal Archives
TMT Pascal Lite - free compiler for DOS
GNU Pascal - free Pascal compiler
FPK-Pascal - free 32-bit Pascal Compiler for DOS - and alternate German mirror, USA mirror #1, or USA mirror #2
Pascal Links from Programmers Heaven
Pascal Source Archives
SWAG Web Site - free Pascal sources and information
Turbo Pascal Programming Page

APL

APL is mainly an oddity (like PL/I) but unlike PL/I, it has a strong following. It's main purpose (and design) is for mathematics - in fact, APL is merely an implementation of a mathematical symbolic algebra that someone created - the "language" existed on paper before it was ever conceived of as a computer language. It even looks like algebra.

MicroAPL - sellers of APL.68000 Level II (for 68K Macintosh)
The Toronto APL Special Interest Group - also maintainers of the Toronto Toolkit - APL Utilities Archives
Vector - a popular British APL Magazine
APL2000, Inc. - now owners of the former STSC APL*PLUS
The APL Archives and the J Archives at the University of Waterloo
The SIGAPL APL & J Software Library
Rex Swain's APL Information
Jim W's APL Information
SIGAPL

BASIC

BASIC, like COBOL, suffers from a poor reputation, but it is even less deserving of this reputation than COBOL is. The main complaints against BASIC all revolve around poor implementations of the language; many implementations (such as Waterloo BASIC) proved that a very powerful BASIC could be created and used.

The Beginner's Basic Homepage
O'Basic
The Basic Archives
PowerBASIC and Other BASIC Resources (Macintosh)
FutureBASIC (for the IBM PC)
BASIC Compilers and Interpreters
TrueBASIC (for the IBM PC)
Chipmunk Basic Home Page - lots of links on this page for a freeware Mac BASIC
Carl & Gary's Visual Basic Home Page

Postscript

HTML and the Web

HTML Validators

INvalidated HTML! - re: controversial HTML 3.2
A Kinder, Gentler Validator
WebLint by Neil Bowers - including Web Gateways to WebLint
Free Validator (to download) from Spyglass

HTML Help and References

WWW and Internet Manuals and Demos
All Things Web
Web Reference
HTML Help, including a nice (and downloadable) HTML 3.2 (Wilbur) Reference
Rx HTML
HTML Resource
HTML Quick Reference
HTML Sources from Yahoo
The HTML Writer's Guild
The Style Factory - nice resource for HTML writers
The Ten Commandments of HTML FAQ
HTML Bad Style Page
Web Mastery

HTML Guides and Introductions

Web Weaver's Guide to HTML
A Beginner's Guide to HTML from the National Center for Supercomputing Applications (NCSA) - also home of Mosaic
Gilpo's How To Make Links (H.T.M.L.)

HTML Tools

Virtual Library of World-Wide Web Development

HTML Graphics

HTML Resources and Links

HTML Resources at the HTML Writer's Guild
HTML Links in english and spanish

Crusade Against Browser-specific HTML Extensions

BrowserCaps - Catalog of HTML Supported by Different Browsers
Web Page Backward Compatability - by DJ Delorie, creator of DJGPP, a 32-bit C/C++ compiler for MSDOS
Arguing With Customers - deceptive title: well-written paper on the virtues of not using browser-specific HTML code
Best Viewed With Eyes - no proprietary HTML here!
NOTScape - multilingual!
Down with Proprietary HTML!
Best Viewed with Any Browser - Campaign for a Non-Browser Specific WWW (and multilingual!)