Change a light switch?

[Amber]

Hello,
I am not an electrician just a keen DIY enthusiast. This question sounds a little daft I know but I just wanted to update my light switches which I thought would be a like for like switch. But I came across a loop in the pull switch (photo attached) I changed the one in the bathroom, including the loop, but I would like to know why the loop, the one in the toilet turns the light and fan on, the exisiting switch has four terminals the new only three? again why the loop, I know electricians will know this, I have looked at other switches in the house and see this on others, I just want to understand what it does. This is my first post as I searched the web for an answer, please help me understand. Thanks

 

[Johno]

which pic am i looking at?

 

[antimatter]

Switched live for the fan possibly, when the light is switched on, the power is then sent to the fan to come on at the same time, if the fan stays on after the light is switched off, then it has a timer overun function also.

Hope this helps

 

[Hawk81]

The top pic looks like a 2 way switch.The looped cable does not serve any purose if the switch was wired correctly. The loop cable could be removed and the cable the link is in with moved to were the loop is. The second pic looks like a double pole switch.

 

[Amber]

Thanks for your replys, the first picture with the 3 red wires including the loop is the bathroom which does not operate the fan, though I think it is supposed to.
the second is the toilet which does operate the fan which does run on after turning it off.

 

[Amber]

Just been looking at something else, I want to turn the pond lights off on a timer so I thought I would take a look behind the switches. I think this may help me understand the loop. More Pictures attached, 812 shows all the cables coming. 811 shows the switches for the electric gate, path and tree lights and then 810 shows a feed from a common of the previous to loop into the common on the pond lights to supply a live to the lights which is then L1 out L2 in. So from this I think linking the common gives me a permanent Live as its a double pole switch.
Does this make sense?