Updated the general public homepage with some more useful information.

data/about_meta.yaml

@@ -7,21 +7,21 @@ files: [
     name: public.md,
     slug: public,
     title: I'm a member of the <b>public</b>,
-    subtitle: (non-technical description),
+    subtitle: "(non-technical description)",
     hidden: false
   },
   {
     name: astro.md,
     slug: astro,
     title: I'm an <b>astronomer</b>,
-    subtitle: "(SPH, gravity accuracy, etc.)",
-    hidden: true
+    subtitle: "(hydro scheme, accuracy, tests, physics modules, etc.)",
+    hidden: false
   },
   {
     name: cs.md,
     slug: cs,
     title: I'm a <b>computer scientist</b>,
-    subtitle: "(technical code description)",
-    hidden: true
+    subtitle: "(technical aspects, algorithms, parallelization, etc.)",
+    hidden: false
   }
 ]

data/public.md

@@ -2,59 +2,73 @@
 
 ## What is SWIFT?
 
-SWIFT is a Smoothed Particle Hydrodynamics code for Astrophysics. What does
-that even mean? It is a computer program designed for running on supercomputers
-that simulates forces upon particles due to two main things: gravity and 
-hydrodynamics (forces that arise from fluids rubbing against each other).
-This turns out to be quite a complicated problem as we can't build
-computers large enough to simulate down to an atomic level. This means 
-we need to re-think the equations that describe the particles and how they
-interact. It turns out that we must solve the equations that describe these problems
-numerically, which requires a lot of computing power and fast computer code.
-
-We use SWIFT to run simulations of Astrophysical objects, such as galaxies.
-We do this to test theories about how the Universe came about and evolved from
-the big bang up to the present day!
+SWIFT is a hydrodynamics and gravity code for Astrophysics. What does
+that even mean? It is a computer program designed for running on
+supercomputers that simulates forces upon matter due to two main
+things: gravity and hydrodynamics (forces that arise from fluids such
+as viscosity).  This turns out to be quite a complicated problem as we
+can't build computers large enough to simulate everything down to the
+level of individual atoms. This implies we need to re-think the
+equations that describe the matter components and how they interact
+with each-others. In practice, we must solve the equations that
+describe these problems numerically, which requires a lot of computing
+power and fast computer code.
+
+We use SWIFT to run simulations of Astrophysical objects, such as
+galaxies or even the whole Universe.  We do this to test theories
+about what the Universe is made of and evolved from the Big Bang up to
+the present day!
 
 <div class="videowrapper"><iframe width="100%" height="100%" src="https://www.youtube.com/embed/UJYV6f8SwdQ" frameborder="0" allowfullscreen></iframe>
 </div>
 
 ## Why create SWIFT?
 
-We created SWIFT for a number of reasons. The primary reason beings that we want
-to be able to simulate a whole Universe! This has been attempted before (see
-[the EAGLE Project](http://icc.dur.ac.uk/Eagle) and [the Illustris project](
-http://www.illustris-project.org) for more details), but the codes used to do
-this have always been rather slow and difficult to modify. SWIFT aims to remedy
-that by choosing to parallelise the problem in a different way and by
-having a more modular structure than other codes making it easier for users to
+We created SWIFT for a number of reasons. The primary reason beings
+that we want to be able to simulate a whole Universe! This has been
+done before successfully (see [the EAGLE
+Project](http://icc.dur.ac.uk/Eagle) for more details), but this
+simulation used a software which is not tailored for the newest
+super-computers and took almost 50 days on a very large computer to
+complete. SWIFT aims to remedy that by choosing to parallelise the
+problem in a different way, by using better algorithms and by having a
+more modular structure than other codes making it easier for users to
 pick and choose what physics they want to include in their simulation.
 
-The way that supercomputers are constructed is not by having one huge superfast
-'computer', but rather by having lots of different computers that are
-connected together by high-speed networks. Therefore the way to speed up your
-code might not necessarily be to make it 'run faster' on a single machine, but
-rather enable those machines to talk to each other in a more efficient way.
-This is how SWIFT is different from other codes that are used in Astrophysics
-for a similar purpose.
-
-Traditionally, you have each 'node' (computer) in the 'cluster' (supercomputer)
-running the exact same code at the exact same time, and at the end of each bit
-of the problem they all talk to each other and exchange information. SWIFT does
-this a little differently, with each node working on different tasks than
-others as and when those tasks need to be completed. This (theoretically)
-should cut down on the time when a node is sitting and waiting for work, which
-is just wasted time and electricity!
+The way that super-computers are built is not by having one huge
+super-fast 'computer', but rather by having lots of regular computers
+(only a tiny bit better than what is available at home!)  that are
+connected together by high-speed networks. Therefore the way to speed
+up your code might not necessarily be to make it 'run faster' on a
+single machine, but rather enable those machines to talk to each other
+in a more efficient way. This is how SWIFT is different from other
+codes that are used in Astrophysics for a similar purpose: the focus
+is on distributing the work to be done (the equations to be solved) in
+the best possible way across all the small computers that are part of
+a super-computer.
+
+Traditionally, you have each 'node' (computer) in the 'cluster'
+(supercomputer) running the exact same code at the exact same time,
+and at the end of each bit of the problem they all talk to each other
+and exchange information. SWIFT does this a little differently, with
+each node working on different tasks than others as and when those
+tasks need to be completed. SWIFT also makes the nodes communicate
+with each others all the time and not only at fixed points, allowing
+for much more flexibility. This cuts down on the time when a node is
+sitting and waiting for work, which is just wasted time, electricity
+and ultimately money!
 
 ## What is SPH?
 
-Smoothed Particle Hydrodynamics (SPH) is a method of calculating the forces
-between fluid elements. Let's say that we want to simulate some water and a wave
-within it. Even a liter of water has 100000000000000000000000000 particles in it.
-To store that much data we would require a computer that as 100 trillion times as
-much storage space as *all of the data on the internet*. It's clear that we need
-a more efficient way of simulating this water if we are to have any hope!
+Smoothed Particle Hydrodynamics (SPH) is a method of calculating the
+forces between fluid elements (gas or liquids). Let's say that we want
+to simulate some water and a wave within it. Even a liter of water has
+100000000000000000000000000 particles in it.  To store that much data
+we would require a computer that as 100 trillion times as much storage
+space as *all of the data on the internet*. It's clear that we need a
+more efficient way of simulating this water if we are to have any
+hope!
 
-It turns out that we can represent the water by many fewer particles (let's say
-about 1000) if we can smooth over the gaps between them efficiently. Smoothed
+It turns out that we can represent the water by many fewer particles
+if we can smooth over the gaps between them efficiently. Smoothed
 Particle Hydrodynamics is the technique that we use to do that.