Unity simple shader

Shader "MyFirstShader" 
{
    
    Properties
	{
    
        _Color("color1",Color)=(1,1,0,1)
		_BaseMap("Base Map",2D)="white" {
    }
    	}
	
	SubShader
	{
    
		Pass //pass You can use more than one pass
		{
    
	     HLSLPROGRAM //HLSL Can be replaced by GLSL

		#pragma vertex Vertex // Declare functions  // Vertex shader 
		#pragma fragment Pixel // Fragment Shader   Pixel shader 

	     half4 _Color;// Declare variables 
	     sampler2D _BaseMap;

	     
	     //model Transform the local space of an object into world space 
	     //view  Through the change matrix of the camera, from the world space to the camera space 
	     //projection  Projection transformation to screen space 

	     #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

        struct Attributes
        {
    
        	float4 vertex:POSITION;
        	float2  uv : TEXCOORD0;
	        
        };

	      struct Varyings
        {
    
        	float4 positionCS:SV_POSITION;
        	float2  uv : TEXCOORD0;
	        
        };
	     
	    #if 0 
	    float4 Vertex(float4 vertex:POSITION) :SV_POSITION // Vertex shader  float4 The type of variable entered  vertex Variable name 
	     //: Later, we will talk about the clipping space position associated with the vertex shader  SV It means system value Values in the system 
		{
    
	 
		float positionMS=	mul(UNITY_MATRIX_M, float4(vertex.xyz,1.0));
		float positionCS=	mul(UNITY_MATRIX_M, float4(positionMS.xyz,1.0));
	 
		return 	positionCS;
			
		// TransformObjectToHClip(vertex); // It can also be done through TransformObjectToHClip Return directly to the cutting space 
		// return TransformObjectToHClip(vertex);
	 
	    }
	     #endif

	     Varyings Vertex(Attributes IN)  // Vertex shader  float4 The type of variable entered  vertex Variable name 
	     //: Later, we will talk about the clipping space position associated with the vertex shader  SV It means system value Values in the system 
		{
    
            Varyings OUT;
			OUT.uv=IN.uv;// If you don't need to UV Make changes with input uv
			OUT.positionCS=TransformObjectToHClip(IN.vertex.xyz);
			
            return OUT;
	    }
	     
	     

		half4 Pixel(Varyings IN) : SV_TARGET //SV It means system value
	     //SV_TARGET Indicates the color of the last pixel output 
	    {
    
	    	half4 color;
	    color.rgb=tex2D(_BaseMap,IN.uv).rgb*_Color;
	    	color.a=1;
		return color;
	
	    }
		ENDHLSL
	    }
	
	
	}


}