In fact, these are commonly used shortcuts for sharing websites in Japan. They are the same as those on various Chinese websites where you can choose various ways to share with friends

For example, if you take a photo With a photo, you can choose 1. ツイートする (Tweeting, just like sending a Weibo to tell your friends in China)

2. シェアする (Share to Facebook, That is, share it on facebool)

3, チェック (click to mixi, mixi is a large daily social network in Japan, somewhat similar to China's Kaixin.com)

4, *** Yes ( This probably means sharing with friends on the current website)

In fact, the focus of the logo on your picture is not the meaning of the word, but the small size of the icon’s logo

The bird-like one is Twitter, the letter f refers to facebook, and the letter m refers to mixi