please tell me with some example

Bump Maps are used to give a Model more depth without actually having a significant impact on the Performance.

Basically they're giving the Illussion that the Model is bumped in certain places

so, how do i draw Bump Map ?

for TB texture
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is it using some Color Code ?

and how it works

for TB texture ?

You can have it generated here : http://cpetry.github.io/NormalMap-Online/

normally you don't draw ones but that doesn't mean you cant....

and, for ToriBash,

what is Bump Map texture name ?

normal texture name : l_biceps.tga , head.tga , etc
Bump Map :

If I recall correctly, you need to add "_bump" to the filename. Eg: head_bump.tga

This thread should explain it all: http://forum.toribash.com/showthread.php?t=560526