Hi @willstr1, great question! I’m an Arduino enthusiast too.
Twitter introduced OAuth several years ago when we transitioned to API v1.1 and all of Twitter’s API endpoints require authentication, even if they are read-only operations. There are actually three levels of authenticated access - read-only, read/write (for posting Tweets), and read/write with DMs (for access to a user’s DMs). The code in the post you’ve found there is using the older v1 of the API and you’d get a 401 or 410 error if you tried to use it.
OAuth is a bit complicated to deal with on an Arduino due to the limited resources. The Twitter library that is available on the Arduino Playground actually delegates all the work to a server, which does the hard work of authentication and signing requests. Unfortunately it only provides the ability to post Tweets, not read them…
One thing to note is that there’s no requirement for your Arduino to be hardwired, you can absolutely use a wifi shield - I’ve done that before many times. All you’ll really want is a TCP/IP + HTTP stack and that would work fine with the library I just pointed you at.
OK - so how can you display / read Tweets in your Arduino project? there are a bunch of examples around. What they have in common is largely that the Twitter communication piece is done on another device (in Java, Perl, PHP etc). Here are a couple I found… if you replaced the “read from serial line” piece to have your Arduino grab the results via Wifi then they would fit the bill.
I’m also a huge fan of Node-RED, which would be another way of doing this (have a Node-RED flow get the Tweets, and send them to the Arduino)