haha,,,,,,Gud question,,,,logical and questioning doubts that are rarely asked,see there is no hard and specific rule to use them as such. But that is all predefined and a random to a lot extent and moreover see they are defined as such done by one of the oldest contributers towards this field There is not A huge thing like u use i for complex number Z for integers special signs for ur integration derivation and e for euler no. and all that i j and k are one after other a b c have names for another things related to same concept hence we do use i j k just for sake of ease of ours and our own selfs only

Explanation:

nope , there is no logic in naming of unit vectors

this signs used to give the direction to vector

i cap , j cap , k cap , is a famous notation for direction of any vector

along x ,y,z axis respectively

therefore it is used in many books

infact many people don't use caps instead they use dots as they preferred

to them

this unit vector helps us to understand the representation of vector in its 3d or 2d components

so next time one can use f cap g cap t cap in his her own imagination ,as there is no boundation