Assembly Language

What's up with the varying syntax? I hate how there's multiple ways to structure everything.

......................... ,--,-,
........,--,......_..../( ,'')'-'~--,
......./::,-',',')(,,''-, /:::_::::::::\
.......\://(.\-':-,.>. ||:/. ):::::::::|  >>13
......(/.)...--~'/....)|\ .....--,::-''
,-,,--~--,::.::/,---,/./: |....,-'
'-,,.'.'.-~'''¯//....,/./ :/...\
....--.,--',¯...>--':: :/....|
.....\('''''')'-,.)./:::: /,,..../
......\,\''',,\-/./:--''' (_\./-,
......,--\;;;;;;/........ ,-'.\,/
.....//::-,,,,,,-' ' ''' '`
.....\\::/::/