Experimental design involves planning experiments to obtain valid and objective conclusions while minimizing errors and costs. Key aspects of experimental design include selecting treatments, specifying the layout, assigning treatments to experimental units, and collecting observations for analysis. Common types of designs include completely randomized designs, randomized complete block designs, Latin square designs, and factorial designs. Analysis of variance techniques like t-tests, z-tests, F-tests, and Duncan's multiple range tests are used to analyze experimental data and compare treatment means. Proper experimental design helps maximize information gained from experiments.