linux - What's the difference between apt-get and aptitude?

I don't get why there are two different programs in a minimal install to install software. Don't they do the same thing? Is there a big difference? I have read everywhere to use aptitude over apt-get but I still don't know the difference

Answer

aptitude is a wrapper for dpkg just like apt-get/apt-cache, but it is a one-stop-shop tool for searching/installing/removing/querying.
A few examples that apt might not supply:

$ aptitude why libc6
i   w64codecs Depends libc6 (>= 2.3.2)
$ aptitude why-not libc6
Unable to find a reason to remove libc6.


$ aptitude show libc6
Package: libc6
State: installed
Automatically installed: no
Version: 2.9-4ubuntu6
Priority: required
Section: libs
Maintainer: Ubuntu Core developers 
Uncompressed Size: 12.1M
Depends: libgcc1, findutils (>= 4.4.0-2ubuntu2)

Suggests: locales, glibc-doc
Conflicts: libterm-readline-gnu-perl (< 1.15-2), 
tzdata (< 2007k-1), tzdata-etch, nscd (< 2.9)
Replaces: belocs-locales-bin
Provides: glibc-2.9-1
Description: GNU C Library: Shared libraries
 Contains the standard libraries that are used by nearly all programs 
 on the system. This package includes shared versions of the standard 
 C library and the standard math library, as well as many others.