True strain

True strain measures how much a material stretches relative to its original length, accounting for continuous deformation during stretching. Unlike simple strain, which looks at the initial and final lengths, true strain sums up the incremental deformations throughout the process, providing a more accurate picture of the material's behavior under stress. It is calculated by adding up the small percentage changes in length as the material is stretched, effectively capturing the actual deformation the material experiences, especially during large strains where simple measurements may not be sufficient.