Like by using hidden sense in words, logo or sentence.
These are called subliminal stimuli. They work as "subconscious order" and they are more efficient with repetition and subtle reinforcement words group. Wikipedia article is not very complete about sentence subliminal stimuli.
To understand better it takes to search deeper...
I found two article on how they works, the first, the second (more detailed).
Everyone conscientiously or unconsciously use these.
Unfortunately, their is some people using these consciously with bad intention or reward in exchange.
The only way to be protected from theses messages is by knowing their exist and how they works.
Like by using hidden sense in words, logo or sentence.
These are called subliminal stimuli. They work as "subconscious order" and they are more efficient with repetition and subtle reinforcement words group. Wikipedia article is not very complete about sentence subliminal stimuli.
To understand better it takes to search deeper...
I found two article on how they works, the first, the second (more detailed).
Everyone conscientiously or unconsciously use these.
Unfortunately, their is some people using these consciously with bad intention or reward in exchange.
The only way to be protected from theses messages is by knowing their exist and how they works.