What is Divx?
DivX is the name given to a video codec (a piece of software encoding and decoding video) and is based on the MPEG-4 compression format. MPEG-4 is a new standard of video compression that is both high quality and low bitrate. DivX files
are usually only a fraction (around 15%) of the size of a standard DVD, even at 640x480 resolutions, making them the
best home video format thus far. DivX files only take half the time to encode, and yet at the same time are much smaller in size than MPEG-1 or 2 - due to their incredible compression technology. Some have even called MPEG-4 the "MP3 of the video world".
Quality ranges from Net-streaming to DVD standard or better.

.IFO file The .IFO (and backup .BUP) files contain menus and other information about the video and audio .

.VOB & .AOBfile .VOB files (for DVD-Video) and .AOB files (for DVD-Audio) are MPEG-2 program streams with additional packets containing navigation and search information
Bitrate Also known as Bit rate. The speed at which digital audio and video content streams from a source, such as a file, to be rendered properly by a player, or the speed at which binary content in general is streamed on a network

Codec :Short for compressor/decompressor. Codecs are various types of computer algorithms that are applied to audio, video, and image files to compress the size of the files

What is an ASPI driver?
An ASPI driver is required for digital audio extraction (DAE) . Windows 95 or 98 comes with the ASPI manager pre-installed, while NT does not. To tell if you have an ASPI manager installed, look for a file called WNASPI32.DLL in your Windows system directory (c:\windows\system or c:\winnt\system32 are common locations).#1 DVD ripper comes with ASPI driver for win32 V4.7 .After installing #1 DVD ripper you can find it in the start menu group of #1 dvd ripper.