'Slider' does not contain a definition for 'value' - slider

Question

I want to make some project when I slide the UI slider will appear some text. But after I finish my coding, the error appears.
error CS1061: 'Slider' does not contain a definition for 'value' and no accessible extension method 'value' accepting a first argument of type 'Slider' could be found (are you missing a using directive or an assembly reference?)
But if I put in a new project, the error did not come out. When I import asset the error comes again.
Here is my code:
public class TextControl : MonoBehaviour {
public Slider Food;
public Slider Calories;
public Text States;
public Text Question;
public void Update()
{
wordShown();
}
public void wordShown()
{
if (Food.value >= 0.5f)
{
if (Calories.value >= 0.5f)
{
States.text = "INACTIVE, UNHEALTHY";
Question.text = "What changes can make him be active and healthy?";
}
else if (Calories.value < 0.5f)
{
States.text = "ACTIVE, HEALTHY";
Question.text = "What should he do to maintaian his fitness?";
}
}
else if (Food.value < 0.5f)
{
if (Calories.value >= 0.5f)
{
States.text = "INACTIVE,UNHEALTHY";
Question.text = "What classes of food should have consume by this person?";
}
else if (Calories.value < 0.5f)
{
States.text = "ACTIVE, HEALTHY";
Question.text = "High calorie associated with what type of food?";
}
}
}
}

Answer 1

Ok i got the solution.
there is actually a script named slider.cs. So I changed it to sliderscript.cs. Slider is the name for the property of unity. we cannot use the property as our script name.

Answer 2

I got another solution.
use UnityEngine.UI.Slider instead of Slider because as Kamil Digital said the property slider and script slider somehow conflict.
Example:
Slider MusicSlider; //DOESNT WORK
MusicSlider = musicObj.GetComponent<Slider>();//DOESNT WORK
UnityEngine.UI.Slider MusicSlider;//SHOULD WORK
MusicSlider = musicObj.GetComponent<UnityEngine.UI.Slider>();//SHOULD WORK