which namespaces do i need to learn for desktop and server

hello friends, i am a beginner programmer still learning the basics.

 

i wish to learn C# and hope to get a job in the future as a programmer.  but i am very confused as to what which namespaces to learn thoroughly since there is an overwhelming amount of namespaces and classes in .net.

 

my ambition is just to get a job as a basic c# programmer. 

 

but i do personally wish to be proficient in desktop apps, and one day hope to make a web spider. 

 

can you please advise me which namespaces/classes i should learn.

 

thank you