Question

what is the differences between 'file' and 'file name'​

Answer 1

$\mathbb\red{HELLO\:DEAR\:USER}$

$\Large{\underline{\underline{\sf{\red{Req}\pink{uir}\green{ed}\:\purple{Ans}\blue{wer}\:\orange{:-}}}}}$

For datafiles, it does not make a difference - both statements will reference the data file in your current directory. (For example, cat filename and cat ./filename are semantically identical.)

$\Large{\underline{\underline{\sf{\red{B}\pink{e}\green{\:}\:\purple{Brai}\blue{nly}\:\orange{!}}}}}$