What is PECS? (Picture Exchange Communication System)
PECS (Picture Exchange Communication System) was developed almost 40 years ago in 1985 by Andy Bondy and Lori Frost. In a nutshell, for children, a child takes a picture of something they want/need to express and gives that picture to an adult (or anyone) who then responds to that request. It's a way of helping a child express themselves, reduce frustration, make choices, ask for something.
I think of it as a 'menu' using pictures and written text to help express oneself at a time when words are not available. Since then technology allows us to use devices such as iPads to help a child communicate with their family, peers and teachers.
This is a low-tech AAC device (Augmentative and Alternative Communication). Some children will develop words while using AAC (if that's something they were going to do). Not all children use/develop words/oral speech and that is okay.
It doesn't mean that anyone has done anything wrong or that there was a lack of trying or effort. It simply means that speaking/using oral language is naturally harder for that individual and to imply that they aren't trying or are 'being lazy' could be compared to saying that someone who uses crutches to walk is a 'lazy walker', it is simply not the case.