The medium is the message. - Marschall McLuhan

What McLuhan meant by statement The medium is the message?

I think that any medium produces a message by its content which is interpreted in mind of a "receiver" who has its own culture, social, education associations. Anyway, every medium communicates a message but can be interpreted in different ways. The "transmitter" should have a responsibility to avoid misunderstanding of what is communicated what is in the message.

The medium itself can be used for "good" thing or can be also exploited for manipulation!

Visual communication

......., so visual communication need to be aware of possible interpretation and find ways to prioritise the interpretation they want. For example the designers of the 'no walking on the grass' sign could have added some text or focused their image on the idea of walking than just the shoe.

.....Talk to someone from a different culture and the associations might be very different. A visual communication draws on a shared visual culture and reflects it back, as it does so, it may reinforce, emphasise or change the reference points it draws on.

Deconstruction by Sorina Higgins - Language is inherently unreliable

https://www.youtube.com/watch?v=RUm-47oMWU4