Like on Electrum wallet, if you want to open a channel, you will be warned how lightning on Electrum is experimental, which is the reason of the advice not to put large amount of bitcoin on lightning channels. So, making use of it with just little amount of Bitcoin is better, even on any other wallet because the lightning network is still in its experimental stage till now. You will need to learn more about lightning network, you can read these guides:

A Beginner's guideline to Bitcoin Lightning Network
The Lightning Network FAQ
Electrum Lightning Network walkthrough

Lightning network will be good to pay on stores and places you visit often in which you trust the owner of the store and places and allows you to open a channel with them. You buy what you want to buy like coffee, and you will pay right at the moment even before leaving the coffee shop, I do not think this should be a problem. And you can decide to close your channel anytime you want in which your Bitcoin will be transferred into your on-chain wallet address and be stored on blockchain.

node going offline is only a problem if it's more than a few minutes/hours. Most internet outages don't last more than a few hours.

to steal funds from you, your node needs to be offline for weeks (i.e. after the timeout period in the part of the contract where 1 node closes the channel on their own). Who gets disconnected from the internet for that long? Maybe only if you can't pay your ISP bill, but it sounds like you've got more serious problems in your life than your lightning node


future improvements to lightning will make these problems less serious anyway, but for now, just make sure your node is running ok and that your bills are paid.

Assuming Alice and Bob wants to make use of lightning network, Bod is the owner of one coffee shop, Alice is the customer. Both of them will have to open a channel, the channel is just a 2-of-2 multisig, which means both of them will have the knowledge the transfer of any particular amount they both agreed upon.

If they both agree to put 0.005 btc each on the channel

Alice: 0.005 btc
Bod: 0.005 btc

That means they both have 0.005 btc + 0.005 btc = 0.01 btc on the channel. Assuming Alice went to Bob's shop for coffee and he or she paid 0.0001 btc, the money will be deducted from Alice btc to Bob Btc on the channel. Which means Alice will have 0.0049 btc as 0.0001 btc is transferred by her on the channel while Bob will have 0.0051 btc for the coffee Alice paid for and so on until anyone of them closes the channel.

You can try use Electrum wallet and use very low amount of Bitcoin with your friend to understand this better using this guide.

Go and read the links above, irrespective of the sender or the receiver, both parties have an opened channel.

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Note that on-chain miners fee will be demanded for while opening and closing a channel, but you can open and close channel when fee is low. Lightning network fee is very low after you have opened a channel already.

alright. thank you all for clarifying

and thx for that bestchange link @charles-tim

^ there describes the opening of another flaw

people cannot predict what they may want to buy in the next week or month.
so the supposed opening a channel with a coffee shop and then closing a channel premise is flawed because it ends up being spending 2 onchain(open+close) just to buy coffee

the real thing is people dont end up having lots of small channels with their temporary retailer.
instead they have channels a few hub/spoke/hops away and hop the path to their temporary retailer has value and is online at the point of purchase
this requires the trust and ideals of several people inbetween

also users wont want to set up dozens of accounts splitting up their funds for the hopes of multiple paths. because they end up having to close channels more often to rebalance the funds

EG if you only trust $200..
and a coffee is $4 thats only 50 coffees in a 1 channel route.
but its only 10 coffess if you split your funds over 5 channels.
thus costing you more onchain to open 5 channels of only 10 coffees each. and then close them to move funds to the channels that have good routes
(you cant predict the goodroute vs bad route before hand)
studies have seen 50-90% of payments fail due to not having viable routes.
this study showed a 60% success rate for a single $4 coffee
buying 2 coffees is a 50% chance of success
buying 10 coffees for colleagues in your office.. 10% chance of success


what people end up doing is getting rid of the headaches of multi channal fund splitting hop model network.
and instead deposit funds into a service and let the service manage the channels offchain and reaggregate funds offchain as the funds are with the manager.

this will result in centralisation

i certainly can see where this can happen, that is why it is important to selfhost

i draw the comparison to email, which is decentralized as a protocol, but got centralized (not completely) because people tend to use google or microsoft for that, that is why i have my own mailserver and let my family use it too

i will do the same with the lightning node i am setting up right now

will send you a pm in some minutes


c-lightning (there are enough people using lnd imo)