Pipette is an old science instrument .it the simplest equipment just like straw .this instrument is mainly used when u want to use more solution to add(mix'') like 50ml where us in rubber(back baloney) push u c't be steady hand   
A pipette ,or chemical dropper is a laboratory tool  commonly used in chemistry , biology and medicine to transport a measured volume of liquid . it comes in various types and designs with differing level of accuracy and precision from a single piece glass pipettes to more complexive pipettes . it works by creating a vacuum above the liquid holding chamber and releasing this vacuum to draw up and dispense liquid . measurement accuracy varies greatly depending upon different styles.
now i can give only this information . you can add many images describing them .