Risk in software development refers to unforeseen events that can positively or negatively impact a project's progress, results, or outcomes. There are several types of risk, including schedule risks from wrong time estimations, budget risks from incorrect costing, operational risks from failed processes or systems, and technical risks such as changing requirements. Key sources of risk include user involvement, unrealistic expectations, staff turnover, and an unclear project scope or specifications. Risk management involves identifying, assessing, prioritizing, and taking coordinated actions to minimize threats and maximize opportunities. Actions include measuring risks, minimizing their impact, communicating about risks, and continually monitoring and updating risk assessments.