Introduction threads are threads created by new users, usually being their first thread or even their first post, where they, as per the title, introduce themselves to the community they were about to take part in. While common on other forums, some even having a dedicated forum section or boards for introduction threads, they are an uncommon sight on Facepunch. While the rules of General Discussion suggest that such threads be made in Fast Threads, normally new users immediately head towards the content that interested them on the forum and post in the designated forum section, sub-forum, or thread.
Every so often, however, some introduction threads can quickly grow in popularity for a variety of reasons, whether it be from the tone of the new user's posts or due to their perceived innocence.
I didn't see an 'introductions' thread.... ?
I didn't see an 'introductions' thread.... ? is an "introduction" thread created by a new member under the name of Artichoke; it was instantly mocked by other members for being an obvious troll thread, made by an actual troll.
New Member To Facepunch
In stark contrast to Artichoke's thread, New Member To Facepunch, created by JuiceJuicy, was seen in a more positive light. Being pinned for a short period, users quickly accepted the newly joined user. This didn't last long, as he soon went on a shitposting spree that earned a ban. A subsequent meltdown in the Refugee Camp led to a permaban. 
New User Says Hello!
In a similar vein to JuiceJuicy, New User Says Hello!, created by Scribble-tier, it was similarly viewed positively like the previous example was initially. Due to being the second introduction thread posted in General Discussion, which disallowed them, both threads were moved to Fast Threads by postal.
- Fast Threads - I didn't see an 'introductions' thread.... ?: https://facepunch.com/threads/1584597
- General Discussion/Fast Threads - New Member To Facepunch: https://facepunch.com/threads/1586095
- Refugee Camp - I... got banned again?: https://facepunch.com/threads/1586913
- General Discussion/Fast Threads - New User Says Hello!: https://facepunch.com/threads/1586511