Are terms of service legal contracts? Are ToS considered contracts in and of themselves, enforceable under contract/civil law? Generally I'm talking about the Common Law systems in the major regions (UK, North America and Oceania). Anything that applies to (majority of) Europe would be fine too.
Providing they meet the basic requirements (see What is a contract and what is required for them to be valid?) then they are binding contracts. Consideration is not an issue: the site provides the content, the user provides eyeballs on it. Consent is the major stumbling block. Online Terms of Service are either presented as browsewrap or clickwrap or sign-up wrap. A browsewrap provides notice of the terms of service but there is no specific user assent to them. A clickwrap requires the user to check a box specifically about agreeing to the terms (with or without user registration). A sign-up wrap presents user registration with a "Sign up" and provides notice to the terms at the point of service but doesn't have a check button specifically for the terms. As an example, Stack Exchange provides two types of wrap. For the casual user, there is a Legal link at the bottom of the page - a browsewrap. If you sign-up, you go to a page that says "By clicking "Sign up", you agree to our terms of service, ..." - a sign-up wrap. Whether a Terms of Service is an enforcable contract depends on whether the user provided notice, whether the user gave consent and whether enforcing the agreement is conscionable. Clickwraps and sign-up wraps have the advantage over browsewraps in the first two of these. Assuming that the contract terms are unremarkable (i.e. they are within the range of "normal" for that type of contract) a clickwrap will normally create an enforcable contract - Forrest v Verizon and Motise v America Online being the relevant case law. Browsewraps are more problematic: Specht v Netscape said no contract but where the browsewrap is shown prominently and repeatedly they can form an enforceable contract - Hubbert v Dell and Cairo v CrossMedia Services. Zaltz v Jdate was a sign-up wrap and did create an enforceable contract. All of these turn on the facts of how the information was was presented to the user. For example, in Meyer v Kalanick the Second Circuit said: Where there is no evidence that the offeree had actual notice of the terms of the agreement, the offeree will still be bound by the agreement if a reasonably prudent user would be on inquiry notice of the terms.[sic] So, in general, Terms of Service are enforcable as a contract if a reasonably prudent user could, on inquiry (e.g. by clicking a link), make themselves aware of the terms. This also explains why skrinkwraps (when software came on actual physical media in a shrink-wrapped box with the terms inside) were not enforcable - a reasonably prudent user could not inform themselves of the terms without unwrapping a product they didn't yet own.
No enforceable contract can contain illegal clauses and work Contracts can not remove some rights and never can bypass obligations. Talking to the police at times is a requirement by law, as is taking to the labor board. Responding to a subpoena is legally forced by the court. An NDA might limit the amount what you can say, and a contract might limit who you can sue, but can not ban you from suing at all. In germany, a contract that tries to curtail such requirements would be Sittenwidrig and make all clauses that try to limit the rights fully Void and nill ab initio - in fact, it can be used as evidence against the drafting party that they tried to do so. So to stay legal and keep the clause working in the limited fashion where it is not demanded, the clause cuts the contract to explicitly exclude such situations.
Here is a substantial collection of interpretive canons; this article discusses rules vs. canons. This article discusses contract interpretation from both the perspectives of drafting and litigating. These are all from the perspective of common law systems. This article (in English) and this chapter (English, paywall) reminds us that French contract law is different, to which I would add this which focuses on the French subjective theory of contracts – starkly distinct from the common law theory. This page (en français) will probably be of most interest to you. The 2016 modification to the civil code added art. 1190 (and other articles) which says Dans le doute, le contrat de gré à gré s'interprète contre le créancier et en faveur du débiteur, et le contrat d'adhésion contre celui qui l'a proposé which is contra proferentem. The Latin name is not officially assigned to this law, and being a new addition to French law, it's too early to tell if it will be so named in French legal practice.
Yes. The formation of a contract requires (among other things) that the parties intend to be legally bound. Their sending the offer from a corporate email address shows this. You replying in the same way shows your intention. Signatures are optional. Consider, verbal contracts are binding; how do you sign those?
If two parties agree to the terms of an exchange, then there exists an enforceable contract. A signature is not needed to create a contract. However, an intent to negotiate a contract is not, per se, a contract. Absent some specific and explicit measures (which for major deals may be codified in an MOU or LOI that itself contains contractual terms), if you can't reach an agreement on terms then there is no contract. It's up to the particulars of "the verbal agreement to start the hiring process" whether an agreement on exchange has been reached, or merely proposed. E.g., "You and I agree that I will pay you $X in exchange for Y due Z" is a contract. "You and I agree that we'd like to work together, and we'll hammer out the terms X, Y, and Z by the end of the week" is merely a proposal to contract, not an actual contract. Of course, this doesn't mean you're immune to liability for failing to reach a contract in this hypothetical: you can always be sued!
Yes. This type of contract is called a license. Lawyers write them.
Variations of contracts must be consented to by all parties. This means that if the company sent your friend varied terms, it would have included means by which she would have consented - this may be by continuing to use a service. You cannot unilaterally change the terms of a contract. You could try to charge the company PoS terminal storage fees, but it's highly unlikely to be enforceable if they don't agree to it. In theory if they are aware of the change and they accept them in some way then they are bound to the terms just as she would be, even if they later claimed that they were not aware of them. There is some precedent - in Russia - for this with a bank and it made the news some time ago. There's plenty of cases in which people who don't read EULAs or loan contracts thoroughly are still forced to honour their obligations to their creditors under them.
I was told that when you sign something in the UK, then it is your signature, no matter what name you are using. So if you sign a contract with my name, then it's your signature and you are bound by the contract. Things might be invalid because you signed and not me. For example, if you sign a contract selling my car in my name, then that contract is not valid. If some document needs signatures of two witnesses, and you sign with your name, then with my name, then there are no two signatures. As far as I know, signing under a false name is not in itself criminal, but might very well be supporting fraud, for example, and might therefore be illegal. The contract for the sale of my car, signed by you using my name, would very likely be part of fraud and therefore criminal.