obstacle

An obstacle is anything that blocks or impedes movement, progress, or achievement. Obstacles can be tangible, such as rocks, fences, or fallen trees, or abstract, such as lack of information, conflicting requirements, or bureaucratic hurdles. The word comes from the Latin obstaculum, from ob- “toward” and stat- “standing,” and entered English in the 15th century.

Obstacles are commonly classified by context. Physical obstacles are natural features or human-made barriers that hinder passage. Logistical obstacles arise from access, scheduling, or resource constraints. Informational or cognitive obstacles involve knowledge gaps, ambiguous goals, or miscommunication. Obstacles can be temporary or permanent and may vary with the capabilities and aims of those who encounter them.

In sports and recreation, obstacles form the basis of obstacle courses, hurdle events, steeplechase, and parkour, challenging competitors to overcome barriers under certain rules. In everyday life and problem solving, obstacles are impediments to goals that require analysis, planning, and perseverance to surmount, often by acquiring resources, adjusting strategies, or mitigating risks.

In technology and robotics, obstacles are objects in the environment that autonomous systems must detect and avoid. Sensing methods such as cameras, radar, and lidar, together with path-planning algorithms, enable obstacle avoidance and safe navigation. The general concept of an obstacle also appears in fields such as project management and policy, where impediments to progress must be understood and addressed to achieve objectives.