[Koha] Koha Upgrades

Dear Koha community, We currently have the 3.0 version of Koha.  It's new to us , and we are just learning the program.   We are about to start lots of data entry next week.  What are the advantages of the 3.1 upgraded version?  Should we upgrade before we start lots of data entry?  I know some of you mentioned re indexing once you have upgraded.  What does this involve? Thanks for your input. Janet Deavor St. John Catholic School North Charleston, SC 29405