Tint, shade, and tone are ways of describing colors.
Tint is when you mix a color with a small amount of white. This makes the color lighter and seems to have more of a bright and refreshing feeling. Imagine a bowl of strawberry ice-cream mixed with whipped cream to make it look lighter and softer.
Shade is when you mix a color with a small amount of black. This makes the color much darker and creates a feeling of depth as well as giving the impression of a more subdued look. Imagine a glowing red fire ball that fades gradually into darker shades of red until it becomes almost dull or even similar to black.
Tone occurs when you mix a color with a small amount of gray. This creates a softer and more muted version of the original color. Imagine if you take a bright blue paper and mix it with just a little gray, the blue will seem dull or dusty instead of being a bright blue.
So, in summary, tint makes colors lighter, shades make colors darker, and tones make colors more toned down or muted.