1080i: A high-definition video format that has 1080 lines of vertical resolution and uses interlacing. More info: 1080i

1080p: A high-definition video format that has 1080 lines of vertical resolution and uses progressive scanning. More info: 1080p

16x9: A widescreen aspect ratio that is 16 units wide by 9 units high. More info: Aspect Ratios

2:3 Pulldown: A method of converting 24fps film to video by repeating one film frame as three video fields, then repeating the next film frame as two video fields.

3D: Three-dimensional, or having appearance the appearance of three dimensional depth. 3D images can refer to stereoscopic images (one image for each eye) or computer-generated images based on three-dimensional modeling. More info: 3-D

3GP: A video format based on MPEG-4, used for mobile devices such as cellphones. More info: MPEG-4

4:1:1: A video compression ratio in which the chroma (colour) is sampled at one quarter the rate of luminance (brightness). More info: 4:1:1

4:2:2: A video compression ratio in which the chroma is sampled at one half the rate of luminance. More info: 4:2:2

4:4:4: A video compression ratio in which the chroma is sampled at the same rate as luminance. More info: 4:4:4

4x3: The traditional television aspect ratio, 4 units wide and 3 units high. This aspect ratio is slowly being replaced by 16x9. More info: Aspect Ratios

4x3 Safe: A method of shooting widescreen footage while still retaining a "safe area" that can be cropped and used for 4x3 aspect ratio. More info: Aspect Ratios

5.1 Audio: A surround sound system that provides five separate audio signals: Left, middle, right, rear left, rear right. An additional low frequency (LFE) channel is also provided.

720p: A high-definition video format that has 720 lines of vertical resolution and uses progressive scanning. More info: 720p