Read and write. Think of the term "literacy rate" it refers to how much of a population can read and write.
Answer: it’s network protocol
Explanation:
There are pros and cons to using special characters in email subject lines. Generally, marketers report higher open rates.
Some report better engagement, but many don’t.
There are also reports of special characters causing problems with deliverability, mostly because spammers became very fond of special characters for a while.
