OS X Terminal: 'ls' shows program but then says command not found? I am trying to start MongoDB from the terminal. When I navigate to the folder and hit 'ls', all the applications show up but when I type in the name of the application( 'mongod'), it says it is not found!

Abes-MacBook-Air:bin abe$ ls

bsondump    mongodump   mongoimport mongorestore    mongostat
mongo       mongoexport mongooplog  mongos      mongotop
mongod      mongofiles  mongoperf   mongosniff

Abes-MacBook-Air:bin abe$ mongod

-bash: mongod: command not found


What is going on?
The executable is in your current working directory. Therefore you need to add ./ to your command. So try ./mongod.

See this UNIX StackExchange question for details and background:
Why do we use “./” to execute a file?