Document that true==1 and false==0 (#33252)

* Document that true==1 and false==0

* Update base/docs/basedocs.jl

Co-Authored-By: Stefan Karpinski <[email protected]>

* Update basedocs.jl

* jldoctest

Author: stevengj

base/docs/basedocs.jl

@@ -1432,6 +1432,24 @@ Unsigned
     Bool <: Integer
 
 Boolean type, containing the values `true` and `false`.
+
+`Bool` is a kind of number: `false` is numerically
+equal to `0` and `true` is numerically equal to `1`.
+Moreover, `false` acts as a multiplicative "strong zero":
+
+```jldoctest
+julia> false == 0
+true
+
+julia> true == 1
+true
+
+julia> 0 * NaN
+NaN
+
+julia> false * NaN
+0.0
+```
 """
 Bool