What is the difference between a Leftist and a Liberal?
A group of people with extreme left-wing viewpoints, who are often violent. The term is most often used by right-wingers to describe various anti-capitalist and pro communist groups in the United States, such as the 1960s students and hippies, and many New Left groups like SDS LNSM SWP CPUSA ML ACU WSA PRA PRSC during the Vietnam War.
Leftists are more likely to be old school liberals or Socialists than actual communists but not always true. Liberalism is a political philosophy which stresses individual rights on social issues while maintaining more conservative stances on economic issues. On a spectrum it would lean to the left but is never as radical as leftists.