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Machine wash your garment if the label contains a symbol of a three-sided container with wavy lines on top. Think of this symbol as your washing machine filled with water to help you remember what it means. You can machine wash as normal, without any special considerations.  If this symbol has one line under it, use the permanent press wash cycle.  If this symbol has two lines under it, use the gentle wash cycle.  If this symbol contains one dot, wash it in cold water.  If this symbol contains two dots, wash it in warm water.  If this symbol contains three dots, wash it in hot water.  If this symbol contains a number, wash it in water the temperature (in degrees Celsius) of that number (e.g., if the number is 30, wash the garment in water with a temperature of 30 degrees Celsius, or 86 degrees Fahrenheit). You should hand wash your garment if the label contains a washing symbol with a hand in it. You should not put items with this symbol in the washing machine, as the fabric may be too delicate. Generally, you should not hand wash items at a temperature higher than 40 degrees Celsius (104 degrees Fahrenheit). Do not wash your garment if it contains the washing symbol with an X through it. This goes for both machine washing and hand washing. Instead, take the garment to the dry cleaner to ensure the fabric is cleaned appropriately.

Summary:
Identify when to machine wash your clothes. Identify when to hand wash your garment. Identify when a garment cannot be washed.