It's effort to attain one's goals in a manner that interferes with other's attaining their goals. When it's one sided, it's sabotage or espionage.
Conflict exists at many levels.
Conflict becomes increasingly important as the stress they experience from not attaining their goals becomes increasingly unbearable, threatening to those values they hold most dear. As conflict becomes more unbearable, more costly means are used to attain goals. USA Vietnam involvement Estimating costs relative to the progress made by alternative strategies is one of key abilities of leadership. Unless leaders can do this successfully, they are very likely to fail to attain their goals. Conflict will be with us as long as people have values and goals that can be achieved only at each other's expense.