The export command makes the shell variable named VARIABLE visible to subshells. This means that any child process that is spawned from the current shell will inherit the value of VARIABLE. The export command does not need a dollar sign ($) before the variable name, as that would expand the variable to its value. The set command only affects the current shell and does not export the variable to subshells. The env command can be used to run a command in a modified environment, but it does not export the variable to subshells either.Reference:

[LPI Linux Essentials - Topic 105: Shells, Scripting and Data Management]

[LPI Linux Administrator - Exam 102 Objectives - Topic 105: Shells and Shell Scripting]

The /etc/localtime file is used to configure the system-wide timezone of the local system that is used by applications for presentation to the user. It should be either a symlink to or a copy of a timezone information file that contains the binary data for the configured timezone. The timezone information files are located under /usr/share/zoneinfo/ and are named after the geographic regions and cities, such as Europe/Berlin or Etc/UTC. The timezone identifier is extracted from the symlink target name of /etc/localtime, so it is recommended to use a symlink rather than a copy.The timezone can be changed by using the timedatectl command or by creating a new symlink to the desired timezone file123.Reference:

How to Set or Change the Time Zone in Linux | Linuxize

localtime(5) - Linux manual page - man7.org

localtime(5) --- Arch manual pages

The iconv command is used to convert the encoding of a file from one character set to another. A character set is a collection of characters that are assigned numerical values called code points. Different character sets may use different numbers of bytes to represent each character, and may have different mappings of code points to characters. For example, ASCII is a single-byte character set that encodes 128 characters, while UTF-8 is a variable-length character set that can encode over a million characters. The iconv command can convert between many different character sets, such as ASCII, UTF-8, ISO-8859-1, etc. The basic syntax for using the command is as follows:

iconv [options] -f from-encoding -t to-encoding input-file > output-file

The -f option specifies the encoding of the input file, and the -t option specifies the encoding of the output file. The input file is read from standard input, and the output file is written to standard output, unless specified otherwise.The iconv command can also list all the supported character sets with the -l option1234.Reference:

How To Use the iconv Command on Linux - How-To Geek

iconv command in Linux with Examples - GeeksforGeeks

iconv - convert file encoding from one character set to another | Linux ...

Using iconv to change character encodings - FileFormat.Info

The locale setting of the operating system is a set of environmental variables that defines the language, country, and character encoding settings (or any other special variant preferences) for the applications and shell session on a Linux system12. The locale setting usually consists of at least a language code and a country/region code, such as en_US for English (United States) or fr_FR for French (France).The locale setting also affects things such as the currency symbol, the thousands separator, the decimal point, the date and time format, the collation order, the paper size, the telephone number format, and many other values formatted in accordance with the language or region/country12. However, the timezone is not contained in the locale setting of the operating system. The timezone is a separate setting that determines the local time of the system based on the offset from the Coordinated Universal Time (UTC) and the daylight saving time (DST) rules. The timezone can be different from the country/region code in the locale setting, for example, a user can have a locale setting of en_US but a timezone of Asia/Kolkata.The timezone can be viewed and modified by using the date, timedatectl, or tzselect commands .Reference:12

The -type option of the find command allows you to specify the type of file you want to search for. The argument l (lowercase L) will match files that are symbolic links, which are special files that point to another file or directory. Symbolic links are also known as soft links or symlinks. For example, the commandfind /home -type lwill find all the symbolic links in the /home directory and its subdirectories.