Meaning of 'high-level overview' in a Maths talk? I am a first year Maths PhD student in Singapore.
As I am going to give my first talk at a Mathematics conference soon, I look for  some tips on how to give a good talk.
While googling,  I come across Terrence Tao's blog post entitled 'talks are not the same as paper'.
In the post, he stated in third paragraph that, 


  Instead, a talk should complement a paper by providing a high-level and more informal overview of the same material, especially for the more standard or routine components of the argument; this allows one to channel more of the audience’s attention onto the most interesting or important components, which can be described in more detail.


I have difficulty understanding the meaning of 'high-level'.
An illustrative example:
Let's say you have been working for a very long time on a great paper in which you finally manage to construct a widget which has some amazing properties, which have important consequences for some other area of math.

Now, most of the paper consists of the construction which is extremely deep and technical (this is, after all, why nobody else had been able to construct this widget before you).

To give a high level overview of your work, you need to talk mainly about what the widget does, rather than how it is constructed. Talk about these properties and the amazing consequences to other areas in generic terms that can be understood by everyone.

Maybe towards the end, you can talk a bit about the construction. But you should still keep it high-level, meaning that you can talk for example about the main ingredients ("we use a construction analogous to the one for constructing wadgets, but whack it with a hammer in certain places to make it fit our needs"). But leave out any actual technical details.