This thesis conducts a focused literature review on online communities, centering on Stack Overflow, employing social network analysis and graph algorithms. It examines the evolving landscape of health information quality within the digital ecosystem, emphasizing the challenges posed and the multifaceted nature of quality. The significance of online communities, notably Stack Overflow, as hubs for social interaction and knowledge sharing is underscored. Proposing advanced approaches, the thesis introduces an ensemble deep learning model for traffic flow forecasting, an efficient multi-objective optimization method for influence maximization, and a graph convolutional neural network-based approach for link prediction.