In depth tutorials for UE4?

https://wiki.unrealengine.com/Save_System,Read%26_Write_Any_Data_to_Compressed_Binary_Files
https://docs.unrealengine.com/latest/INT/Engine/Rendering/ParticleSystems/Optimization/Results/index.html
https://docs.unrealengine.com/latest/INT/Engine/Blueprints/Overview/index.html
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How can I turn off splitscreen mode with several locals players? - Programming & Scripting - Unreal Engine Forums
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https://docs.unrealengine.com/latest/INT/Programming/Basics/ConfigurationFiles/index.html

https://docs.unrealengine.com/latest/INT/Programming/Development/CompilingProjects/index.html

https://docs.unrealengine.com/latest/INT/Engine/Blueprints/UserGuide/Arrays/index.html
https://docs.unrealengine.com/latest/INT/Engine/Blueprints/UserGuide/Arrays/ArrayNodes/index.html

https://docs.unrealengine.com/latest/INT/Programming/UnrealArchitecture/Reference/Functions/index.html
https://docs.unrealengine.com/latest/INT/Programming/UnrealArchitecture/Reference/Functions/Specifiers/index.html
https://docs.unrealengine.com/latest/INT/Programming/UnrealArchitecture/Reference/Classes/index.html

https://docs.unrealengine.com/latest/INT/Gameplay/Input/index.html

https://docs.unrealengine.com/latest/INT/Gameplay/index.html
https://docs.unrealengine.com/latest/INT/Gameplay/Framework/QuickReference/index.html

https://docs.unrealengine.com/latest/INT/Gameplay/Framework/Pawn/index.html

https://docs.unrealengine.com/latest/INT/Gameplay/HowTo/RespawnPlayer/Blueprints/index.html

https://docs.unrealengine.com/latest/INT/Engine/Physics/Vehicles/VehicleUserGuide/
https://answers.unrealengine.com/questions/38960/blueprintimplementableevent-in-level-blueprint.html

https://forums.unrealengine.com/showthread.php?1047-Lets-Make-Weapon-in-Blueprint-from-Blank-Project
https://docs.unrealengine.com/latest/INT/Gameplay/DataDriven/index.html
https://answers.unrealengine.com/questions/91531/how-to-use-the-gameinstance-bp-to-send-info-to-oth.html
https://www.unrealengine.com/blog/blueprint-networking-tutorials
https://forums.unrealengine.com/showthread.php?2004-Blackboard-Documentation

https://docs.unrealengine.com/latest/INT/API/index.html

https://wiki.unrealengine.com/Interfaces_in_C%2B%2B
https://wiki.unrealengine.com/Slate,_Hello
https://docs.unrealengine.com/latest/INT/Programming/Animation/AnimNodes/index.html
https://docs.unrealengine.com/latest/INT/Engine/Animation/NodeReference/SkeletalControls/index.html
https://docs.unrealengine.com/latest/INT/Engine/Rendering/Materials/LayeredMaterials/index.html

//if you want to use variables in CPP and blueprint, do this:

//for a Variable named AAA of class type BBB, you would write:

//inside the YYY.h class:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "ZZZ")
BBB AAA;


//if you want to define a function in CPP that can be redefined in blueprint, do this:

//for a function named XXX inheriting from a class named YYY, you would write:

//inside the YYY.h class:
UFUNCTION(BlueprintNativeEvent, BlueprintCallable, Category = "ZZZ")
void XXX();

//at the end of the YYY.CPP file:
void YYY::XXX_Implementation()
{
  //add code here
  AAA.doStuff();
} 

//the "_Implementation" suffix for the function name is only needed if you use "BlueprintNativeEvent", and if you want to call that function from CPP, you just call " XXX(); " and not " XXX_Implementation(); "