July 26, 2016 at 03:34AM

Today I Learned: 1) ...the difference between TCP and UDP. Both are protocols for transmitting data over the internet. UDP (User Datagram Protocol) is a lightweight, relatively simple protocol with a simple header and not a lot else. It's cheap to set up, super fast, and totally un-guaranteed to work (it's a "best effort" protocol). TCP (Transmission Control Protocol) is a much more heavyweight protocol that emphasizes security and transmission reliability over raw speed. In TCP, two communicating entities set up a channel with a sender on one end and a receiver on the other. The sender sends out packets over this channel, and the receiver transmits back a receipt of each packet to let the sender know that the packet made it through. The sender will wait until it gets the receipt, and if it doesn't get such a receipt (in the event of packet loss of either original packet or the receipt packet) it will re-send the packet until it does work. This type of communication makes TCP super slow relative to UDP. For many applications (i.e., email), that's fine -- data accuracy is much more important than data speed, in those applications. For data-heavy or time-sensitive communication, as in voice chat, UDP is better because it is less prone to terrible slowdowns. 2) The scientific name of the llama is "Lama glama". I can't get over this fact. I just can't. 3) England has a power station, the Dinorwig power station, that effectively exists entirely to run the nation's tea kettles. See here: http://ift.tt/2amJRkq. The Dinorwig power station is actually a giant hydroelectric battery. When lots of power is available on the grid, Dinorwig pumps water into an elevated reservoire. When additional power is required, Dinorwig opens up sluices on the water reservoires and uses them to spin its turbines. Why? Dinorwig was actually built to solve an issue with nuclear plants, back when the UK was poised to build a lot of nuclear power plants. Nuclear plants apparently can't really run at much less than peak output, which means that a lot of the time they'll be wasting lots of power. Stations like Dinorwig can store this power for use during spikes, or can let nuclear plants shut down for a while to increase efficiency. Much of the UK's nuclear plans didn't hatch (although something like a sixth of England is powered by nuclear these days), so Dinorwig doesn't really serve its original purpose. It's still good for handling power usage spikes, though. The most common cause of such spikes is when a major network program goes to advertising, which can prompt a significant fraction of England's population to turn on their water kettles at once. Thus, one of the most important factors in Dinorwig's operation is the nation's network broadcasting schedule. Thanks to Michael LeFew for pointing me to this.