What is the difference between grep commands:
grep text* ==> does not give any result
grep text * ==> gives result
grep requires (at least) two arguments -- what you are searching for, and where you are searching for it. If the second argument is not provided, then it will use
grep text* is waiting for
stdin to provide it something to search through.
grep text * is searching through all the files in the current directory and returning the results.