Dive into GPU programming with Julia in this comprehensive 3-hour workshop from JuliaCon 2021. Explore three major GPU programming packages: CUDA.jl for NVIDIA GPUs, AMDGPU.jl for AMD GPUs, and oneAPI.jl for Intel GPUs. Learn various approaches for GPU programming, from user-friendly generic array operations to performance-focused hardware-specific kernels. Cover topics including GPU architecture, parallel programming models, array and kernel programming, profiling techniques, and common issues. Engage with practical case studies on image processing, machine learning, and random number generation. Gain hands-on experience solving real-world problems like the heat equation using GPUs. Conclude with a sneak peek at the Enzyme automatic differentiation framework and a Q&A session on future developments in Julia GPU programming.