Weather vs Climate
Weather is the condition in the atmosphere for a short period of time. Climate is how the atmosphere "behaves" over a relatively long period of time. For example weather is like a storm would be weather but a rain forest being tropical.
A thermometer is used for telling and measuring the temperature. It is typically sealed in a glass tube where at the bottom there is a bulb of either mercury or alcohol that rises and falls with the temperature.
An anemometer is an instrument for measuring the speed of wind or any current of gas. Most of the time they have three or four cups attached to a wheel that spins when the wind blows counting the number of times it spins and then calculating the speed.
A barometer is an instrument used to measure atmospheric pressure. There is air pumped inside of the thing that moves the needle telling you the pressure.
A hygrometer is an instrument used for measuring the humidity of the air or a gas. Whenever it is dry outside the hair or plant fiber inside the hygrometer tightens up and the arrow moves one way, but when it is wet outside the hair loosens and the arrow moves the other way.