There have been growing concerns about information disorder in recent years due to false information either intentionally promoted (i.e., disinformation) or accidentally shared (i.e., misinformation) as well as harmful information (i.e., mal-information) circulating online. While the problem of false or harmful information is not new, the problem in the digitally connected world has presented an unprecedented challenge in terms of its scale and complexity. In particular, algorithms are known to add an increased level of complexity to the issue by playing an ambivalent role. Various forms of information disorder can be created, spread and amplified by algorithms, whereas algorithms can also mitigate the problem by detecting such information and helping content moderation decisions. This chapter will review the literature about information disorder and algorithms, with a specific focus on the impact of algorithms on polluted information flow, and discuss how to fight against algorithm-driven information disorder.