from: http://wiki.linuxquestions.org/wiki/Linux_software_equivalent_to_Windows_software

When migrating to Linux from Windows, a common question is "Where can I get a program for Linux that is similar to XYZ program on Windows?" Fear not! Listed below are programs that could be considered roughly equivalent to certain popular Windows applications.

Contents

[hide]

Networking

Windows apps   ↓ Linux apps   ↓ Description   ↓
Microsoft Internet Explorer, Firefox, Netscape, Opera, Lynx, etc.

Epiphany, Firefox, Galeon, Konqueror, Lynx, Mozilla, Nautilus, Netscape, Opera

Internet browsers for the World Wide Web.
Outlook Express, Outlook, Thunderbird, Pegasus, Lotus Notes

Kontact, Evolution, Thunderbird, Claws Mail

Email clients.
ICQ, MSN Messenger, AIM (AOL Instant Messenger), Trillian, Pidgin

Mercury, Pidgin (formerly Gaim), Kopete, aMSN, KICQ, Gabber, Centericq

Instant messaging software.
Microsoft Netmeeting

Gnomemeeting

Microsoft HyperTerminal

minicom

FileZilla FTP Client, WS FTP, Bullet Proof FTP, CuteFTP

FileZilla FTP Client, GFTP, KFTP (KFTPGrabber), Kasablanca, FireFTP, Konqueror, KBear, CrossFTP

FTP client's for browsing an FTP servers.
mIRC

Konversation, KVIrc, XChat, BitchX

Internet Relay Chat client's.
UltraVNC, TightVNC, RealVNC, builtin remote desktop

TightVNC, RealVNC, rdesktop, FreeNX, x11vnc, Synergy, XDMCP, x11 forwarding

Allow remote desktop viewing or control.
MailWasher

KShowmail

Forte Free Agent, Thunderbird, Pan

Thunderbird, Pan, Sylpheed, See More Clients Here

News Reader (Usenet newsgroups)
eMule

aMule

P2P Filesharing software
Azureus, utorrent

Azureus, Qtorrent, Ktorrent, bittornado, Deluge

BitTorrent clients
Skype, Voipbuster

Skype, Linphone, OPenwenGo, Ekiga

VOIP software

Multimedia

Windows apps   ↓ Linux apps   ↓ Description   ↓
Adobe Photoshop[1], Corel Photo-Paint[2], GIMP, GIMPShop

GIMP, GIMPShop, Krita, Pixel (non-free high quality), LightZone (non-free high quality)

Corel Draw[3], Adobe Illustrator[4]

Inkscape

Irfanview, ACDSee

XnView, GQView, Mirage

3D Studio MAX, Blender, Maya

Blender, Maya, Softimage, K-3D

Windows Media Player, PowerDVD

MPlayer, SMPlayer, Xine, Totem, Kaffeine, VLC

SIA Smaart Live

BRP-PACU

Winamp, Sonique, iTunes, aTunes

amaroK, aTunes XMMS, BMP, Audacious, juke, noatun, RhythmBox, xine will play aac and wma, Banshee

Audio Players
Windows Movie Maker, Adobe Premiere Elements, Multiquence[5]

Cinelerra, KDenlive, LiVES, Kino, AviDemux

Video Editing Tools
Audacity, Cubase, CoolEdit, GoldWave[6]

Ardour, Rosegarden,