9 electronic devices for functional sequence, positioning, control and safety in land vehicles, especially material handling vehicles, namely, operating sequence commanding units, positioning devices, operating parameter displays, distance sensors and malfunction indicators; electronic devices for controlling lifting, lowering, rotating, swiveling, and pushing movements of the lifting apparatus of material handling vehicles, namely, lifting level and orientation indicators/displays; electronic devices for commanding, controlling and monitoring the speed of land vehicles, especially material handling vehicles, namely, speed commanding units, acceleration limiters, and parts thereof; data processors and computers for transmitting, converting, and storing electronic data and signals for command and control purposes in land vehicles, especially of material handling vehicles