Infographics are growing in popularity. It simply means ‘information presented in a graphical form’. They are useful because the Internet is increasingly visual.
Most infographics are portrait format – that is, long and thin – rather than landscape format like this one. That’s because it looks better on image-sharing platforms such as Pinterest which have long, narrow columns.
If I’d produced this one, I might omit the full stop after the heading. It’s not necessary, because it’s not a sentence (so it’s breaking the rule). Apart from that (depending what font you choose) full stops in headings look like footballs.
I would quibble about the number 15 in the sub-heading. There are many more punctuation marks than that, including my favourite – the interrobang – shown right. A more accurate sub-heading would therefore refer to the 15 ‘most common’ punctuation marks.