Explain text mode and graphics mode.
In text mode, the screen is internally rendered as text rather than pixels. The screen is divided into a rectangular grid (cell or termed box), with each cell capable of bolding only one character. Text mode with 25 rows and 80 columns of characters is supported by all video standards. Text mode uses mono-space typefaces, which means that each character is the same width on the screen. So that the output can be appropriately aligned. Text mode screen manipulation is faster than its counter part and requires less memory.
