RealPlayer is one of the most popular video player and the only player that can play "real video" files properly - real video files are compact in size. The program has an audio/video library just like Windows Media Player. It can also be used to view web pages and download videos... (
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The program works with the following extensions: 
vob, 
mp4, 
mp3, 
ifo, 
gif, 
swf, 
dat, 
avi, 
flv, 
mkv, 
wma, 
wmv, 
rt, 
mov, 
rv, 
ra, 
qt, 
aa, 
sc, 
rm, 
dv, 
au, 
rf, 
wm, 
rp, 
ogg, 
mmf, 
wmx, 
m4v, 
acp, 
m3u, 
npi, 
wvx, 
rnx, 
mid, 
awb, 
lks, 
3g2, 
bmo, 
mp2, 
ivr, 
mbc, 
3gp, 
rvx, 
mpv, 
bmr, 
m4e, 
obv, 
ssm, 
pls, 
bmt, 
mpa, 
wbs, 
la1, 
lar, 
mpe, 
ram, 
rmp, 
rax, 
aac, 
mps, 
aif, 
rts, 
lqt, 
mpg, 
rjs, 
ac3, 
rpl, 
sdp, 
mnd, 
rmi, 
rjt, 
xpl, 
asf, 
smi, 
mns, 
amr, 
rec, 
asx, 
wav, 
rmj, 
wax, 
rmm, 
flc, 
rpm, 
fli, 
cda, 
rom, 
rmx, 
m4a, 
m1v, 
mp1, 
vpg, 
m4p, 
dvd, 
m2v, 
rsml, 
midi, 
3gp2, 
3gpp, 
mpga, 
lavs, 
mpeg, 
aiff, 
smil, 
divx, 
flac, 
rmvb, 
camv, 
audiocd, 
r1m, 
r3t and 
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