In 1999, the French government published a list of recommended French equivalents for English terms related to the Internet. Such intervention of the government in the language may surprise people from other countries. I don't think other French-speaking countries in the world were consulted. For example, Quebecois say butineur for browser, which is not in this list.

I added additional information through formatting. In both languages, italics indicate terms that, as far as I know, are never or almost never used by French people, bold indicates words that are clearly more often used than their counterpart (although their counterpart is used sometimes), and small characters contain miscellaneous remarks.

access provider
      fournisseur d'accès

applet
      appliquette

asymetric (bit rate) digital subscriber line (ADSL)
      raccordement numérique asymétrique, RNA, liaison numérique à débit asymétrique

backbone
      dorsale

bookmark
      signet

browser
      logiciel de navigation, navigateur

chat
     causette

cookie
     témoin (de connexion), mouchard

cracker
     pirate

cybernaut
     internaute

Digital Versatile Disk (DVD)
     disque numérique polyvalent

domain
     domaine

domain name system (DNS)
     système d'adressage par domaines, annuaire des domaines

drag and drop
     glisser-déposer

emoticon
     frimousse

Extranet
     extranet (with no uppercase!)

firewall
     barrière de sécurité, pare-feu

frame
     cadre

frequently asked questions (file) (FAQ)
     foire aux questions, FAQ, fichier des questions courantes, questions courantes

gateway
     passerelle

hacker
     fouineur (lit. Someone who examines something thoroughly and tries to find things that were meant to remain concealed)

hotlist
     liste de signets

homepage
     page d'accueil

hub
     concentrateur

hypertext
     hypertexte, hypertextuel

Infobahn (german)
     autoroutes de l'information

information highway
     autoroutes de l'information

information superhighway
     autoroutes de l'information

Internet Network, Internet
     internet (with no uppercase !)

intranet
     intranet

middleware
     logiciel médiateur

Net
     internet

netcasting
     diffusion systématique sur la toile, diffusion réticulaire systématique, diffusion sur la toile, diffusion réticulaire

newsgroup
     forum (more often used by experienced Usenet users)

news article
     article de forum, contribution

news item
     article de forum, contribution n. f.

news posting
     article de forum, contribution (or simply "post")

on-line data service
     serveur

plug-in
     module d'extension, extension

proxy server, proxy
     serveur mandataire, mandataire

pull technology
     recherche individuelle

push technology
     distribution sélective, diffusion sélective, distribution personnalisée

server
     serveur

smiley
     frimousse

Thread
     fil (de la discussion)

uniform resource locator (URL)
     adresse universelle, adresse réticulaire

viewer
     visionneur

webcasting
     diffusion systématique sur la toile, diffusion réticulaire systématique, diffusion sur la toile, diffusion réticulaire

webmaster
     administrateur de site, de serveur

webpage, web page
     page sur la toile

website, web site
     site (de la toile, sur la toile)

window
     fenêtre

World Wide Web (or simply Web)
     toile d'araignée mondiale, toile mondiale, toile, T.A.M.

(Journal Officiel, March 16, 1999)