Others have pretty much summed it up. Training with a bokuto (wooden sword) is standard at some schools when starting out in order to safely practice proper noto (sheathing) and nukitsuke (cutting while drawing). Sheathing and drawing are actually the two most dangerous components of iaido since that is when the edge of the sword comes closest to the body – most injuries occur here. Some schools start out with an iaito, which does not have a sharp edge, but the tip can still stab you if you are not careful.
Depends on the school and the teacher.
Usually you start out with a bokuto, but in some schools you start with an iaito.
Depends on the school.
Depends on the school, but usually you start with a bokken
Others have pretty much summed it up. Training with a bokuto (wooden sword) is standard at some schools when starting out in order to safely practice proper noto (sheathing) and nukitsuke (cutting while drawing). Sheathing and drawing are actually the two most dangerous components of iaido since that is when the edge of the sword comes closest to the body – most injuries occur here. Some schools start out with an iaito, which does not have a sharp edge, but the tip can still stab you if you are not careful.