Resistance is an essential element of every electronic circuit, so you will work with a lot of resistors as you explore electronics. You can determine the resistance provided by a resistor by examining the color codes that are painted on the resistor.
These little stripes of bright colors indicate two important factoids about the resistor: its resistance in ohms and its tolerance, which indicates how close to the indicated resistance value the resistor actually is.
Most resistors have four stripes of color. The first three stripes indicate the resistance value, and the fourth stripe indicates the tolerance. Some resistors have five stripes of color, with four representing the resistance value and the last one the tolerance.
If you're uncertain from which side of the resistor to read the colors, start with the side closest to the color stripe. The first stripe is usually painted very close to the edge of the resistor; the last stripe isn't as close to the edge.