Haar wavelets.- Application to ODE.- Stiff equations.- Integral equations.- Evolution equations.- Application to PDE.- Fractional differential and integral equations.- Application to optimal control theory.- Buckling of cracked Euler-Bernoulli elastic beams.- Bending and vibrations of elastic beams.- Buckling of functionally graded Euler-Bernoulli beams.- Vibrations of functionally graded Timoshenko beams.- Application to damage detection using machine learning.