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+# Perl
+Perl is a scripting [programming language](programming_language.md) created by Larry Wall in 1987. Originally meant
+for text processing (as a replacement for [AWK](awk.md)) it latter became a general purpose language. It is quite
+[bloated](bloat.md) and has only a single relevant implementation (written in C). Also it is known for its syntax,
+which can be considered as "inelegant" and leading to "write-only" programs, also the extensive use of sigils;
+marks used before identifiers used as a way of communicating the data type of the underlying identifiers; using
+the wrong sigil can lead to unexpected type conversion.
+
+Perl includes powerful [regex](regular_expressions.md) capabilities, although its regex engine is susceptible to catastrophic
+backtracking.
+
+It is shipped by default on most [Linux](linux.md) distributions, so it could be used as a replacement for [shell scripts](shell_script.md)
+in some applications, but writing such a program in a more efficient language such as [C](c.md) is preferred.
+
+## Notes
+### Stricter language and warnings
+This two lines meant to be put at the top of a script serve as boilerplate to make Perl more strict and saner:
+```perl
+use warnings;
+use strict;
+```
+
+### Sigils
+- `$`: scalar value; numbers, strings...
+- `@`: [array](array.md)
+- `%`: [hash table](hash_table.md)
+- `&`: functions; rare in "modern" Perl code.
+
+### Feature toggling
+For its credit, Perl has a decent level of backwards compatibility compared to other scripting
+languages, so some features that may cause problems with older code are disabled by default. Perl
+allows enabling a set of features manually, for example here we enable the `say` function:
+```perl
+use feature 'say';      # this can also be an array of features...
+```
+More conveniently, instead of enabling each feature manually one can simply pick a certain version
+and all of its features will be enabled:
+```perl
+use v5.34;              # enables `say`, `defer`, `try`-`catch` and more...
+```
+
+## Automatically die on any error
+This makes a Perl script commit suicide if any error is raised (akin to Bash's `set -e`):
+```perl
+use autodie;
+```
+
+## Examples
+### Hello world
+```perl
+# with the classical `print`:
+print "Hello, World!\n";
+# with `say`:
+say "Hello, World!";
+```
+
+### As a replacement for `sed`
+It is possible to use Perl as `sed` to benefit from its more powerful regex:
+```sh
+# you can also pass `-i` to do inline replacement, like in sed
+perl -p -e 's/foo/bar/g' files...
+```
+
+TODO
+
+## Resources
+- [Perl official website](https://www.perl.org/)
+- [Perl Maven](https://perlmaven.com/): page containing tutorials and more