Linux is an open-source kernel and usually comes bundled with free and open-source software; however, proprietary software for Linux (software that isn't free and open-source) does exist and is available to end-users. Networking Web browsers FTP clients Firewall (packet filtering) Opendium Web Gateway – part of a content control system targeted at schools Opendium UTM – part of a content control system targeted at schools SmoothWall Corporate – a closed fork of SmoothWall, targeted at enterprise and corporate users Visual traceroute VisualRoute P2P file sharing Loophole (WinMX protocol) – WinMX servers down since 09.2005 MetaMachine eDonkey2000 – latest release from 25.07.2005 (discontinued) μTorrent Server "Hotline" P2P protocol clients/servers GHX Multifunction sound modem programs PrimaFax Fax software Esker Fax Fax2Send FAXCOM Ictfax MessagePlus/Open U-Fax Network maintenance HP Openview agents Routing GateD Distributed computing Portable Batch System PBS Gridworks Instant messaging Discord Skype ICQ Viber Trillian P2P file synchronisation BitTorrent Sync VoIP software Skype Zoom client for Linux alfaview Desktop/system software Work with files Console archivers RAR B1 Free Archiver Desktop search Google Desktop (discontinued) 1.0, released June 27, 2007 File splitters HJSplit for Linux – freeware, also available on other platforms PDF viewers PDF authoring Adobe Acrobat Distiller (discontinued) Cryptography Pretty Good Privacy Scanner utilities VueScan Xvscan last updated in 2000 Antivirus Avast! Antivirus AVG Anti-Virus Bitdefender GravityZone Comodo Group Anti-Virus for Linux Dr. Web F-Prot (not to be confused with F-Secure) Kaspersky Anti-Virus ESET NOD32 RAV Antivirus (discontinued) Sophos Antivirus for Linux Trend Micro ServerProtect for Linux Vexira for Linux Fileserver Vexira for Linux Samba Server Bootloader / Boot manager Hard disk partitioning Acronis PartitionExpert Paragon Partition Manager Backup software PIM / DB / hierarchical notebook with tree view TreePad Lite File hosting service clients Dropbox Mega Drivers Printer drivers Brother Industries Hewlett-Packard (HP) Lexmark International TurboPrint Multimedia Audio/video Digital audio workstations Bitwig Studio Mixbus ocenaudio REAPER (experimentally) Renoise Tracktion MP3 encoding L3enc (discontinued) Score writers Guitar Pro Multimedia players Fluendo DVD Player LinDVD Moovida Pro Musictube PowerDVD for Linux (discontinued) JRiver Media Center RealPlayer (discontinued) Music Dataplore Dataplore CMS energyXT Guitar Pro Loomer Aspect Loomer Manifold Loomer Resound Loomer Sequent Loomer Shift v2 Loomer String MuSing Netease Cloud Music Pianoteq RecordPad Spotify Transcribe! Graphics Graphics viewers/editors Professional graphics editors and photography AfterShot Pro Corel Photo-Paint 9 (discontinued) PaintSupreme Pixel32 Pixeluvo Digital imaging Bibble FX Photo Effects 2D bitmap animation and paint Harmony TVPaint Vector graphics editors Corel Draw 9