Several levels are defined for teletext in ascending order of rendering complexity, although no TV sets currently implement the two most sophisticated levels.
| Level | Description |
|---|---|
| 1 | The initial specifications set out by the BBC, IBA, BREMA in September 1976. |
| 1.5 | Used in Spain. Created by TVE (Televisión Española), is an extended version of the level 1, created to support Spanish special characters and other ASCII-like characters, and colouring modes. |
| 2 | Multi-language text, wider range of display attributes that may be non-spacing, wider range of colours and an extended mosaic pictorial set. |
| 3 | Dynamically Redefined Character Set (DRCS) allowing the display of non-Roman characters (e.g. Arabic and Chinese). Pictorial Graphic characters can also be defined. |
| 4 | Full geometric graphics. It needs computing power to generate the display from a sequence of drawing instructions. The colour palette has 250,000 shades. |
| 5 | Full-definition still pictures allows better quality than video cameras. Modulated onto a carrier. No noise added to the picture during transmission. |
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