Alfred

At its core, Alfred is an application launcher. Instead of clicking on an icon on your dock or searching through your Applications folder, you simply hit a key combination (in my instance, Cmd+Space) to open a text input window. As you input the name of the application you wish to launch, Alfred displays potential matches, limiting the list as you write. Either pressing Return or picking an option with the Command key will open the specified item. In addition to launching programs, you may also access files, folders, emails, and contacts, run online searches, copy/move files and folders, and execute a multitude of other operations. Almost anything stored on your Mac is accessible to Alfred. Alfred learns more about you as you use it to assist you in working more swiftly and effectively.

This is a good starting point, but to get the most out of Alfred, you must get the Powerpack. This enables sophisticated features such as finding contacts, accessing the clipboard history, managing iTunes playing, and connecting with 1Password. The capacity to design workflows is arguably the most significant Powerpack feature. These are multi-step operations that may consist of AppleScripts, shell scripts, Ruby or Python code, etc. If you so want, you may create your own workflows or download workflows that other Alfred users have published.