How to use <apex:inputText>  in Visualforce Page?

<apex:inputText> :

An HTML input element of type text. Use this component to get user input for a controller method that does not correspond to a field on a Salesforce object.

This component does not use Salesforce styling. Also, since it does not correspond to a field, or any other data on an object, custom code is required to use the value the user inputs.

Syntax:
<apex:inputText value="{!inputValue}" id="theTextInput"/>

This tag supports following attributes:

Attribute	Description
accesskey	The keyboard access key that puts the field in focus. When the text box is in focus, a user can select or deselect the field value.
alt	An alternate text description of the field.
dir	The direction in which the generated HTML component should be read. Possible values include "RTL" (right to left) or "LTR" (left to right).
disabled	A Boolean value that specifies whether this text box should be displayed in a disabled state. If set to true, the text box appears disabled. If not specified, this value defaults to false.
id	An identifier that allows the field component to be referenced by other components in the page.
label	A text value that allows to display a label next to the control and reference the control in the error message
lang	The base language for the generated HTML output, for example, "en" or "en-US".
maxlength	The maximum number of characters that a user can enter for this field, expressed as an integer.
onblur	The JavaScript invoked if the onblur event occurs that is, if the focus moves off of the field.
onchange	The JavaScript invoked if the onchange event occurs that is, if the user changes the content of the field.
onclick	The JavaScript invoked if the onclick event occurs that is, if the user clicks the field.
ondblclick	The JavaScript invoked if the ondblclick event occurs that is, if the user clicks the field twice.
onfocus	The JavaScript invoked if the onfocus event occurs that is, if the focus is on the field.
onkeydown	The JavaScript invoked if the onkeydown event occurs that is, if the user presses a keyboard key.
onkeypress	The JavaScript invoked if the onkeypress event occurs that is, if the user presses or holds down a keyboard key.
onkeyup	The JavaScript invoked if the onkeyup event occurs that is, if the user releases a keyboard key.
onmousedown	The JavaScript invoked if the onmousedown event occurs that is, if the user clicks a mouse button.
onmousemove	The JavaScript invoked if the onmousemove event occurs that is, if the user moves the mouse pointer.
onmouseout	The JavaScript invoked if the onmouseout event occurs that is, if the user moves the mouse pointer away from the field.
onmouseover	The JavaScript invoked if the onmouseover event occurs that is, if the user moves the mouse pointer over the field.
onmouseup	The JavaScript invoked if the onmouseup event occurs that is, if the user releases the mouse button.
rendered	A Boolean value that specifies whether the component is rendered on the page. If not specified, this value defaults to true.
required	A Boolean value that specifies whether this field is a required field. If set to true, the user must specify a value for this field. If not selected, this value defaults to false.
size	The width of the input field, as expressed by the number of characters that can display at a time.
style	The style used to display the inputText component, used primarily for adding inline CSS styles.
styleClass	The style class used to display the inputText component, used primarily to designate which CSS styles are applied when using an external CSS stylesheet.
tabindex	The order in which this field is selected compared to other page components when a user presses the Tab key repeatedly. This value must be an integer between 0 and 32767, with component 0 being the first component that is selected when a user presses the Tab key.
title	The text to display as a tooltip when the user's mouse pointer hovers over this component.
value	A merge field that references the controller class variable that is associated with this field. For example, if the name of the associated variable in the controller class is myTextField, use value="{!myTextField}" to reference the variable.

Visualforce Example :

<apex:page standardController="account">
<apex:form id="changeDescription">
<apex:pageBlock >
<apex:pageBlockSection columns="1">
 <apex:inputfield value="{!account.name}"/>
 <apex:inputtext value="{!account.accountnumber}"/>
 </apex:pageBlockSection>
 <apex:commandButton value="Save" action="{!save}"/>
 </apex:pageBlock>
 </apex:form>
 </apex:page>