In science, malleable refers to the property of metals to be bent and extended so that its shape could be changed accordingly. Pressure is usually applied to the malleable material to reshape it like in the case of plastic and leather. Malleable metals like gold and copper, meanwhile, are melted so that it could be bent.
If the term is attributed to a person, malleability refers to a personality trait where one can easily change his taste, temperament and attitude according to the situation at hand. The person could have prepared himself beforehand thus he is said to have easily adapted to the situation, or it is something unexpected yet he easily faces the event and gets through it without much difficulty. A malleable person is not easily flustered since he is emotionally and psychologically-equipped to face uncertainties, get along well with anyone, and easily accept changes and surprises.
It is advantageous to be malleable when one is thrust in unexpected circumstances. For instance, when the family moves into a new neighborhood, it is easier for the malleable person to adapt to the new environment, new home, make friends with the neighbors, and simply fit in. The malleable person could also accept new ideas more readily, and thus could be expected to be more open-minded about things and receptive to different opinions coming from others. I find this true every time I receive criticisms from others. By being malleable, I can accept these criticisms, even the negative ones, and try to use them constructively to improve myself.
Malleability, however, has its disadvantages to the individual. A person may be asked to do something that is morally wrong or against his values and being malleable, it would be easier for him to accept the necessity of the deed rather than hold fast to his values and refuse. The malleable person could easily be convinced with a little persuasion or rationalization from others. Furthermore, when one has done something bad, it is easier for him to move on and not be plagued by guilt. Personally, malleability has caused me to succumb to peer pressure and do things that I regretted later on.
One should learn, therefore, to know when to be malleable and when to be stubborn and unchanging. This personal trait, after all, is not a plus for all situations.