1.8 k ohm 1/4 watt resistor (10 pieces) pack is a passive electrical component that creates electrical resistance in electronic circuits. The list is endless.
The electrical resistance of a resistor or an electrical conductor is a measure of the opposition to the flow of electric current. The SI unit for resistance is the ohm. Any material shows some resistance except superconductors, which have zero resistance. More information about resistance, resistivity and conductance.
Of course, it is possible to make a resistor with very precise resistance, however, it will be insanely expensive. Besides, high precision resistors are relatively rarely used. There are very expensive resistors used for measurements. Here we will talk about inexpensive resistors used in electric circuits, which do not require high precision. In many cases, ±20% of precision is enough. For a 1 kil0 ohm resistor, this means that any resistor with a value in the range of 800 ohms to 1200 ohms is acceptable. For some critical components, the tolerance can be specified as ±1% or even ±0.05%. At the same time, it is hard to find 20% resistors today — they were common at the beginning of the transistor radio era. 5% and 1% resistors are very common today. They were relatively expensive in the past, but not anymore.