Re: type over

I'm new to Mac, so forgive me if this sounds petulant, but ... isn't there
any way to quickly switch between modes? My PC just had a toggle key on
the keyboard. I frequently have to do both while editing a single
do***ent, and this seems way too much work. It's the first thing I've
found that's not easier than the old PC, but it's a biggie for me.