Trim .wav file in ubuntu

1. Install sox command. If don't have it, you can install it by "sudo apt-get install sox"
2. Use sox command with option trim
sox [input file] [output file] trim [from time] [to time]
Example: sox OverviewPart1.WAV Overview.wav trim 0:10 1:21

Solving Desktop effectes could not be enabled

When we use ubuntu, we may want to enable desktop effects because it allows us to do many things such as zoom in and zoom out. We can try to enable desktop effects by going to System > Preferences > Appearance > Visual effects and then click "Normal" or "Extra"

try to enable desktop effects on ubuntu but get the problem "Desktop effects could not be enabled", try to do the following steps:

1. Use command compiz and then you may find out that your video driver is in the blacklist as shown in this picture
2. edit /usr/bin/compiz and put the # at the line that has your video driver specification so that it is not in the black list
Now, try to enable Desktop effects again. You should be able to enable it now :)

Recommended plugins for firefox

There are many plugins for firefox, but we should not install all of them because they may downgrade the performance of firefox.

These are recommended plugins for firefox

1. Adblock Plus - to block all advertisement messages
2. Delicious Buttons
3. Noscript
4. SmarterFox