Khal is a standards based console calendar program, able to synchronize with CalDAV servers through vdirsyncer. It includes both a CLI and a TUI named 'ikhal'.

Libical is an implementation of the iCalendar protocols and protocol data units.

gsimplecal is a lightweight calendar application written in C++ using GTK. Launched once, it pops up a small calendar applet, launched again it closes the running instance. It can additionally be configured to show the current time in different timezones.

By default, date2name gets the modification time of matching files and directories and adds a datestamp in standard ISO 8601+ format YYYY-MM-DD at the beginning of the file or directory name.

Remind allows you to remind yourself of upcoming events and appointments. Each reminder or alarm can consist of a message sent to standard output, or a program to be executed. It also features: sophisticated date calculation, moon phases, sunrise/sunset, Hebrew calendar, alarms, PostScript output and proper handling of holidays.

ddate displays the Discordian date and holidays of a given date. The Discordian calendar was made popular by the "Illuminatus!" trilogy by Robert Shea and Robert Anton Wilson.

ConfClerk is an application written in Qt, which makes conference schedules available offline. It displays the conference schedule from various views, support searches on various items (speaker, speech topic, location, etc.) and enables you to select favorite events and create your own schedule.

At the moment ConfClerk is able to import schedules in XML format created by the PentaBarf conference management system (or frab) used by e.g. FOSDEM, DebConf, FrOSCon, Grazer LinuxTage, and the CCC congresses.

ConfClerk is targeted at mobile devices but works on any system running Qt.

Ccache is a compiler cache. It speeds up recompilation by caching previous compilations and detecting when the same compilation is being done again. Supported languages are C, C++, Objective-C and Objective-C++.

cdrecord converts a CD image in a ".bin / .cue" format (sometimes ".raw / .cue") to a set of .iso and .cdr tracks.

cdrdao records audio or data CDs in disk-at-once (DAO) mode, based on a textual description of the contents. This mode writes the complete disc – lead-in, one or more tracks, and lead-out – in a single step and is commonly used with audio CDs. cdrdao can also handle the bin/cue format, commonly used for VCDs or disks with subchannel data.

Libisofs creates ISO 9660 (also known as ECMA-119) file system images which can either be written to POSIX file objects or handed over to libburn for being written directly to optical media. It can read metadata of ISO 9660 filesystems, manipulate them, and use them to produce new complete file system images or add-on images to be appended to the read file system image. Supported extensions to ISO 9660 are Rock Ridge, Joliet, AAIP, zisofs.

geteltorito can extract the initial/default boot image from CDs (and ISOs) that follow the El Torito specification for bootable CD-ROMs.

Image data is written to standard output by default and all other information is written to standard error.

Cdrkit is a suite of programs for recording CDs and DVDs, blanking CD-RW media, creating ISO-9660 file system images, extracting audio CD data, and more. It's mostly compatible with cdrtools.

GNU Xorriso is a tool for copying files to and from ISO 9660 Rock Ridge, a.k.a. Compact Disc File System, file systems and it allows session-wise manipulation of them. It features a formatter and burner for CD, DVD and BD. It can operate on existing ISO images or it can create new ones. xorriso can then be used to copy files directly into or out of ISO files.

DVDStyler is a DVD authoring application which allows users to burn video files in many formats to DVD discs, complete with individually designed menus. It can be used to create professional-looking DVD's with custom buttons, backgrounds and animations, from within a user-friendly graphical interface.

libMirage is a CD-ROM image access library. It supports the following formats: B6T, C2D, CCD, CDI, CIF, CUE, ISO, MDS, MDX, NRG, TOC. It is written in C and based on GLib. Its aim is to provide uniform access to the data stored in various image formats.

Libcue is a C library to parse so-called cue sheets which contain meta-data for CD/DVD tracks. It provides an API to manipulate the data.

Libcddb is a C library to access data on a CDDB server (freedb.org). It allows you to:

1. search the database for possible CD matches;

2. retrieve detailed information about a specific CD;

3. submit new CD entries to the database.

Libcddb supports both the custom CDDB protocol and tunnelling the query and read operations over plain HTTP. It is also possible to use an HTTP proxy server. If you want to speed things up, you can make use of the built-in caching facility provided by the library.

CDEmu client is a simple command-line client for controlling CDEmu daemon.

It provides a way to perform the key tasks related to controlling the CDEmu daemon, such as loading and unloading devices, displaying devices' status and retrieving/setting devices' debug masks.

cd-discid is a command-line tool to retrieve CDDB discid information from an audio CD.

Libburn is a library for reading and writing optical discs. Supported media are: CD-R, CD-RW, DVD-RAM, DVD+RW, DVD+R, DVD+R/DL, DVD-RW, DVD-R, DVD-R/DL, BD-R, and BD-RE.

The GNU Compact Disc Input and Control Library (libcdio) is a library for CD-ROM and CD image file access. It allows the developer to add CD access to an application without having to worry about the OS- and device-dependent properties of CD-ROM or the specific details of CD image formats. It includes pycdio, a Python interface to libcdio, and libcdio-paranoia, a library providing jitter-free and error-free audio extraction from CDs.

libcdio-paranoia is an implementation of CD paranoia libraries based on libcdio.

Asunder is a graphical audio CD ripper and encoder. It can save audio tracks as WAV, MP3, Ogg Vorbis, FLAC, Opus, Wavpack, and Musepack. It can use CDDB to name and tag each track automatically, and it allows for each track to be by a different artist. Asunder can encode to multiple formats in one session, and it can create M3U playlists.