La Blanca Real Estate Other Lawyer, Texas, page 6

(1) A legal principle that prevents a person from asserting or denying something in court that contradicts what has already been established as the truth. equitable estoppelA type of estoppel that bars a person from adopting a position in court that contradicts his or her past statements or actions when that contradictory stance would be unfair to another person who relied on the original position. For example, if a landlord agrees to allow a tenant to pay the rent ten days late for six months, it would be unfair to allow the landlord to bring a court action in the fourth month to evict the tenant for being a week late with the rent. The landlord would be estopped from asserting his right to evict the tenant for late payment of rent. Also known as estoppel in pais.estoppel by deedA type of estoppel that prevents a person from denying the truth of anything that he or she stated in a deed, especially regarding who has valid ownership of the property. For example, someone who grants a deed to real estate before he actually owns the property can't later go back and undo the sale for that reason if, say, the new owner strikes oil in the backyard.estoppel by silenceA type of estoppel that prevents a person from asserting something when she had both the duty and the opportunity to speak up earlier, and her silence put another person at a disadvantage. For example, Edwards' Roofing Company has the wrong address and begins ripping the roof from Betty's house by mistake. If Betty sees this but remains silent, she cannot wait until the new roof is installed and then refuse to pay, asserting that the work was done without her agreement.estoppel in paisSee equitable estoppel.promissory estoppelA type of estoppel that prevents a person who made a promise from reneging when someone else has reasonably relied on the promise and will suffer a loss if the promise is broken. For example, Forrest tells Antonio to go ahead and buy a boat without a motor, because he will sell Antonio an old boat motor at a very reasonable price. If Antonio relies on Forrest's promise and buys the motorless boat, Forrest cannot then deny his promise to sell John the motor at the agreed-upon price.(2) A legal doctrine that prevents the relitigation of facts or issues that were previously resolved in court. For example, Alvin loses control of his car and accidentally sideswipes several parked cars. When the first car owner sues Alvin for damages, the court determines that Alvin was legally drunk at the time of the accident. Alvin will not be able to deny this fact in subsequent lawsuits against him. This type of estoppel is most commonly called collateral estoppel.

A type of bond (an interest-bearing document that serves as evidence of a debt) that does not require security in the form of a mortgage or lien on a specific piece of property. Repayment of a debenture is guaranteed only by the general credit of the issuer. For example, a corporation may issue a secured bond that gives the bondholder a lien on the corporation's factory. But if it issues a debenture, the loan is not secured by any property at all. When a corporation issues debentures, the holders are considered creditors of the corporation and are entitled to payment before shareholders if the business folds.

A legal claim that one party failed to perform as required under a valid agreement with the other party. For example you might say, 'The roofer breached our contract by using substandard supplies when he repaired my roof.'

A legally binding agreement involving two or more people or businesses (called parties) that sets forth what the parties will or will not do. Most contracts that can be carried out within one year can be either oral or written. Major exceptions include contracts involving the ownership of real estate and commercial contracts for goods worth $500 or more, which must be in writing to be enforceable. (See statute of frauds.) A contract is formed when competent parties -- usually adults of sound mind or business entities -- mutually agree to provide each other some benefit (called consideration), such as a promise to pay money in exchange for a promise to deliver specified goods or services or the actual delivery of those goods and services. A contract normally requires one party to make a reasonably detailed offer to do something -- including, typically, the price, time for performance and other essential terms and conditions -- and the other to accept without significant change. For example, if I offer to sell you ten roses for $5 to be delivered next Thursday and you say 'It's a deal,' we've made a valid contract. On the other hand, if one party fails to offer something of benefit to the other, there is no contract. For example, if Maria promises to fix Josh's car, there is no contract unless Josh promises something in return for Maria's services.

A promise that pledges nothing, because it is vague or because the promisor can choose whether or not to honor it. Such promises are not legally binding. For example, if you get a new job and promise to work for three years, unless you resign sooner, you haven't made a valid contract and can resign or be fired at any time.

The causing of harm by disrupting something that belongs to someone else -- for example, interfering with a contractual relationship so that one party fails to deliver goods on time.

The basis of a contract. Consideration is a benefit or right for which the parties to a contract must bargain; the contract is founded on an exchange of one form of consideration for another. Consideration may be a promise to perform a certain act -- for example, a promise to fix a leaky roof -- or a promise not to do something, such as build a second story on a house that will block the neighbor's view. Whatever its particulars, consideration must be something of value to the people who are making the contract.

Federal laws that prohibit housing discrimination on the basis of race or color, national origin, religion, sex, familial status or disability. The federal Acts apply to all aspects of the landlord/tenant relationship, from refusing to rent to members of certain groups to providing different services during tenancy.