docs: write what-are-bios-files without pronouns

The pronoun pass left this start page untouched. Its old heading keeps
its anchor.

wiki/what-are-bios-files.md

@@ -8,7 +8,7 @@ order: 10
 A console has a small program inside it. It starts first, then starts the game.
 This program is the **BIOS**, also called **firmware**.
 
-<a class="rb-button rb-button-primary" href="../which-pack.md">Get your files</a>
+<a class="rb-button rb-button-primary" href="../which-pack.md">Get the files</a>
 
 An **emulator** is an app that acts like a console. For many consoles, it needs
 a copy of the BIOS. That copy is a file: a **BIOS file**.
@@ -17,14 +17,14 @@ a copy of the BIOS. That copy is a file: a **BIOS file**.
 
 ## How it works
 
-1. You pick a game in your setup's menu.
+1. Pick a game in the setup's menu.
 2. The setup starts the emulator.
-3. The emulator opens the BIOS file in your **BIOS folder**.
+3. The emulator opens the BIOS file in the **BIOS folder**.
 4. The game starts.
 
-If step 3 fails, you see "BIOS missing" or a black screen.
+If step 3 fails, the screen says "BIOS missing" or stays black.
 
-## Do I need one?
+## Which consoles need one? { #do-i-need-one }
 
 - **Yes:** PlayStation 1 and 2, Saturn, Neo Geo, PC Engine CD and many home
   computers.
@@ -49,12 +49,12 @@ another for Europe.
 Some setups check each file's **hash**, a fingerprint of its contents.
 Batocera, Recalbox and EmuDeck report a version they do not expect.
 
-Our files are the versions each setup expects.
+The files here are the versions each setup expects.
 
 ## Can a game start without it?
 
 Sometimes. Some emulators carry their own code in place of the BIOS. Some games
-then glitch or do not start. The real file works best, so we include it.
+then glitch or do not start. The real file works best, so the packs include it.
 
 ## Is it legal?
 
@@ -62,6 +62,6 @@ Laws differ by country. [Is it legal?](legal.md)
 
 ## Next steps
 
-- [Get your files](../which-pack.md)
+- [Get the files](../which-pack.md)
 - [Words used on this site](glossary.md)