What is "Depth of Atomic Objects" ?

*To*: mathgroup at smc.vnet.net*Subject*: [mg96696] What is "Depth of Atomic Objects" ?*From*: ichi <mune9518 at gmail.com>*Date*: Sat, 21 Feb 2009 19:38:28 -0500 (EST)

Hi, The Mathematica Help in A.1.4 says "Atomic objects in Mathematica are considered to have depth 0 and yield True when tested with AtomQ." For example, numeric 4 is Integer and must be a Atomic object. Then I try the function Depth and AtomQ ; Depth[4] returns depth "1". And AtomQ[4] returns "True". Why can the function Depth return depth "0" ? I wonder if meaning of the function "Depth" differs from the word "depth". But I feel somthing strange. How can I understand this ? thanks.