Current line-follower-robot simulation tools often lack the ability to accurately replicate real-world conditions, making them ineffective for testing and optimizing algorithms and inaccessible for educational use. In this scenario, the present study introduces Robosim, a comprehensive line follower robot simulator that mimics physical dynamics, allowing users to develop, test, and refine control algorithms in a virtual environment. The developed RoboSim simulator accepts input in the form of a floor map, which represents the environment in which the robot operates. The map is provided in a structured text format, such as a matrix or grid. Each element in the matrix corresponds to a specific type of terrain or path, with different characters or numbers representing different features. The Robosim simulator comprises key modules, including Map Reader for loading the floor map into a 2D array, Robot Initialization for setting start coordinates, Sensor Simulation for environmental sensing, and Robot Movement for executing control algorithms by adjusting coordinates. Users can implement custom algorithms for testing, with the Position Display module showing the robot's location on the map. The proposed software is a very lightweight simulator designed in C++, which makes it easy to use in computationally restricted environments. Moreover, the computer program, along with sample map files, is freely available for download at https://github.com/Samarth-Godara/Robosim_v1 . The simulator is a versatile tool that can be utilized in a variety of settings. It can be used in educational institutions for teaching robotics and control systems, in research labs for developing and testing advanced robotic algorithms, and in the robotics industry for prototyping and refining line follower robots before physical deployment. Additionally, its user-friendly interface and comprehensive features make it an intriguing tool for hobbyists and enthusiasts to explore and learn about robotic systems.