FLV means FLASH VIDEO. It is a new video format developed with the launch of Flash MX. FLV streaming media format makes online watching video possible with features of quite fast loading rate and rather small size it forms. Nowadays, all online video sites adopt FLV format, and as there're more and more video sites and podcasts sites, FLV as a newly born network format becomes more and more popular. Either Youtube, Google video as current most popular video sharing sites have adopted FLV as technical basis.

MKV is a common video file defined by Matroska Media, a new multimedia package format. The feature of MKV is that it could hold many types of encoded video, audio and subtitles stream.

To convert flv to MKV, please install FLV Splitter and FFDSHOW. Run "regsvr32 FLVSplitter.ax" to register the FLV Splitter. 

Download MKV Converter which can convert FLV to mkv file. Then please install MKV codecs. Select an FLV file, set some parameters such as DivX or XviD as the video compressor,  Microsoft ADPCM as the audio compressor, adjust the resolution, frame rate etc if necessary.

3GP is a video coding format of 3G(3rd Generation)'s streaming media. 3GP is developed especially for mobile phones to adapt to the high transmission speed of 3G network. Though rm format files are also played and mostly in smartphones, 3GP format is a multi-media standard made by 3GPP and is the most popular among mobile phone market at present. 3GP provides the users with high quality video, audio and other contents of multi-media. Besides, 3GP files could also be played on computer with the relative players like Media Player Classic, MPlayer, QuickTime, RealPlayer, etc.

To convert 3gp to mkv easily, please install 3GP codec such as FFDSHOW, or HDX4, or QuickTime Alternative.

3GPP means Generation Partnership Project. 3GPP is the third generation (3G) cell phone system specification between many countries.

3GPP2 means The Third Generation Partnership Project 2: 3GPP2 is a collaborative third generation (3G) telecommunications specifications-setting project, and comprising North American and Asian interests developing global specifications for 3G. 3GPP2 is global specifications for the radio transmission technologies (RTTs).