Customized Module Concept

se send me some examples of cusotmized module and explain it's functionality. what is the work of @ISA, and @INA path?. Please help me on this. Thanks in Advance...!!!!!! Regards, Ayush Kabra

Need help

Hi Team, I need little bit help. i need to sort a file according to its 3rd column and i need the output. can you please help me on this. Input file we can take anyone either .txt or .xls or .csv. Please look into this and help me. Regards, Ayush Kabra