A task is a set of actions assigned to a person or a group. A task accomplishes a job, an assignment or a problem. Tasks can be used at a group level or even at a personal level. Here we differentiate tasks into 2 categories:
Zoho Tasks lets you to add one day tasks where you can create tasks based on time. You can create one day tasks like your business appointments, meetings, conference calls, product demos, etc,. You can also set reminders through pop-up and mail to notify the subsequent tasks.
To create one day task:
Note:

Create a list of tasks and be reminded of them at the right time while you work. Zoho Tasks lets you set a reminder for every task that you create. It is very useful and a user-friendly reminder which is ideal for business use.
Create a reminder and get notified through a pop-up message or a mail when the time is due. 
Tags, yet another useful feature in Zoho Tasks, make it easier for you to organize your list of tasks by category. Zoho Tasks support multiple custom tags. For example, 'Meeting with Manager' task might fit into "Meetings" category and "To do list" category.




Zoho Tasks has been enhanced to give you the ability to tag a task using the drag and drop feature. This is much easier and faster than the other way of tagging tasks. To tag a task, just drag the task and drop it over a tag under the Tags list. You can also select multiple tasks at a time and drop it over a tag.
Note:


Color code your tags to give its own color to differentiate it from the rest of the tags. Color coding makes much easier to find tags at a glance instead of having to search one by one. Here's how you can color code your tag.

Group Tags is similar to Personal Tags where you can assign a tag to a task which is in Group. You can also assign multiple tags to a task. However there are few things that differ from Personal tags.

Recurring tasks are repeating series of tasks that occur regularly. If you run a business, you will have a set of tasks which is to be done every week/month/year. So, in that case it is better to have an option which will automatically remind you on the particular task.
The recurring tasks option in Zoho Tasks automatically generates the same task once the task is completed. The task is generated at the same time that was set for the first one. Given below is a typical scenario where the recurring task feature can be used:
In a company, the Accounts department has to update the salaries of employees on the last working day of every month. A task is set for the 31st of August, which is a Monday. The task title is "Salary Update". Select Advanced and repeat the task Monthly on the Last weekday of every month. Once the task is completed, a repeat task is generated for the 30th of September, which is the last working day of the next month. This repeats for consecutive months.

You can assign tasks to any user in your organization. To assign a task to another user, click the ' + ' icon, select users and click OK. Only the task owner can edit or delete the task.
Definitely, this will be an add-on option for Zoho Mail Suite users. Users can just add their CRM and Projects tasks directly under Zoho Mail Suite Task without having logging-into specific application.
Users can create different categories and can sort them accordingly. This will help the user to create a task and to have them in a categorized way.
Rate the progress of your tasks using different task status. Zoho Business lets you define the following kind of status:
The attendee can change the status of the task to canceled if he wishes to do so.
There are 5 types of priorities in Task. They are Highest, High, Medium, Lowest, Low. The default priority is Medium. The priority can be set when a task is created and also when a task is edited. Task priority defines how important the task is.
Given below are all the five different types of priority and four kinds of status.

Tasks provides users with five different kinds of views. They are:
Tasks can be viewed according to the status of the tasks. Therefore clicking on the All, Pending, Completed, Canceled will show up the respective tasks in the task pane. Each view displays the tasks in that current view setting along with the complete task details
You can also view tasks according to the status of the tasks. Therefore clicking on the All, Pending, Completed, Canceled will show up the respective tasks in the task pane. Each view displays the tasks in that current view setting along with the complete task details.
Reports are generated for all the tasks that are created. A report is based on the following.
Reports are generated for all the tasks that are created. A report is based on the following.
To add a comment to a task, just click on the comment icon which in the tasks list. 
To add a sub-task to an existing task, just hover your mouse pointer over the task list and click on the add subtask icon as shown in the image below This is an additional option where users can add number of sub-tasks without creating a new task each time. 
You can easily import your extensive task list into Zoho Tasks from another application that you are currently using.
To Import Tasks:

To Export Tasks:
You can also export tasks from Zoho Tasks.
To make a quick note of a task, just make use of " Quick Add " option and that will be added to your task list. And later you can modify the task as you want it to be.