Difference between SP_WHO & SP_WHO2

First of all, SP_WHO is a MS-SQL SERVER’s Documented Command while SP_WHO2 is an UnDocumented Command. SP_WHO2 provides more detailed information about Servers running objects as

SPID,Status,Login,HostName,BlkBy,DBName,Command,CPUTime, DiskIO, LastBatch, ProgramName,SPID, REQUESTID

While SP_WHO provides details as

Spid,ecid,status,loginame,hostname,blk,dbname,cmd,request_id