Which came first, Java or Twitter?

Java came first, by 11 years. Sun Microsystems announced Java publicly.

Side by side

Java

Java was announced in May 1995, having started in 1991 as a project called Oak aimed at interactive television — a market that did not exist yet. Its promise was "write once, run anywhere", achieved by compiling to bytecode for a virtual machine rather than to a specific processor. JavaScript arrived seven months later and was named after it purely as a marketing decision; the two languages are unrelated.

Twitter

The first tweet — "just setting up my twttr" — went out on 21 March 2006, and the service opened publicly that July. The 140-character limit came from SMS: a text message allows 160 characters and 20 were reserved for the username. When the limit doubled to 280 in 2017 the SMS constraint had been irrelevant for years.