Twitter is a social networking site, or 'micro-blogging' tool to use a term that seems to have fallen out of favour. It has 126 million daily users (according to figures from February 2019), around 10% the level that Facebook enjoys. Nonetheless it is an important part of the social media ecosystem and seems particularly beloeved by journalists and anyone else who chooses to, or can only, express their thoughts in a limited number of characters. Which reminds me, follow Technically Product on Twitter @technicallyprod