# What is difference between Type{T} and T

**URL:** <https://discourse.julialang.org/t/what-is-difference-between-type-t-and-t/19325>\
**Category:** New to Julia\
**Tags:** type, parametric-types\
**Created:** [January 6, 2019, 3:42pm UTC](https://discourse.julialang.org/t/what-is-difference-between-type-t-and-t/19325 "2019-01-06T15:42:15Z")\
**Posts on this page:** 1\
**Showing post:** 16

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**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [March 11, 2021, 2:50pm UTC](https://discourse.julialang.org/t/what-is-difference-between-type-t-and-t/19325/16 "2021-03-11T14:50:07Z")

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I think you are confusing things. `isa` shows if the **type of the first argument** `<: the second argument`. So does not make sense to me to use `isa` to establish any ordering/tree, you should be using `<:` for it.

```julia
julia> Any <: Type
false

julia> Type <: Any
true

julia> Any <: DataType
false

julia> DataType <: Any
true

```

You should not use `isa` passing a type as the first argument, because it will always be the same as `DataType <: second_isa_argument` because the type of any type will be `DataType`.

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