If you have been on Twitter in the past week, you have probably seen a lot of flags. You may recognize this has to do with the World Cup, but you may wonder how everyone got the memo to post flags. Are they just emojis that are becoming a trend?

Nope. It is all Twitter. Before the World Cup, Twitter reintroduced hashflags, a social media attribute applied during the 2010 World Cup. Every time, a Twitter user types in a three-letter hashtag affiliated with the nation of choice, the flag pops up along with it. The three-letter hashtags are the FIFA abbreviations of the countries.

For example ...

Unless the hashtag is used with the exact three letter, the flag does does not appear. Qasim Zaib of TechEclipse displayed the result of such an error in a series of tweets he made regarding hashflags.

The code #BEH did not trigger a hashflag. The hashflag code for Belgium (missing nation in Group H) is #BEL.

This is far from the only example of a wrong hashtag. More than a week into the World Cup, social media users are unknowingly leaving themselves empty-handed.

Belgium is not one of the common hashflags mistaken. According to Twitter data published on The Wall Street Journal, Cameroon is the most commonly missed hashflag, with 13.8 percent of hashtag attempters punching in the wrong hashtag. While the correct hashtag is #CMR, the most common wrong hashtag is #CAM.

Following Cameroon is Nigeria (#NGA) with 7.2 percent using the incorrect hashtag #NIG. Bosnia and Herzegovina (#BIH) is a near third with 6.3 percent going with #BOS.

Rounding out the top seven missed hashflags are Japan/#JPN (incorrect: #JAP, 4.6 percent), Spain/#ESP (incorrect: #SPA, 4.3 percent), Iran/#IRN (incorrect: #IRA, 3.5 percent) and Switzerland/#SUI (incorrect: #SWI, 3.2 percent).

If it is any consolation prize for Spain getting eliminated from the World Cup, the incorrect hashtag percentage should lower. This summer may feel a little different than the two Euro Championships and One World Cup Championship won in the past six years.

-- Follow Jeffrey Eisenband on Twitter @JeffEisenband.