dcc.Store

```python
from dash import Dash, html, dcc, Input, Output, callback, no_update
import dash_ag_grid as dag
import plotly.express as px
import pandas as pd

app = Dash()

df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/gapminderDataFiveYear.csv')

app.layout = html.Div([
    dcc.Store(id='memory-output'),
    dcc.Dropdown(
        df.country.unique(),
        ['Canada', 'United States'],
        multi=True,
        id='memory-countries',
    ),
    dcc.Dropdown(
        {'lifeExp': 'Life expectancy', 'gdpPercap': 'GDP per capita'},
        'lifeExp',
        id='memory-field'
    ),
    dcc.Graph(id='memory-graph'),
    dag.AgGrid(
        id='memory-table',
        columnDefs=[{'field': i} for i in df.columns],
        dashGridOptions={"pagination": True}
    )
])


@callback(Output('memory-output', 'data'), Input('memory-countries', 'value'))
def filter_countries(countries_selected):
    if not countries_selected:
        return df.to_dict('records')
    dff = df[df['country'].isin(countries_selected)]
    return dff.to_dict('records')


@callback(Output('memory-table', 'rowData'), Input('memory-output', 'data'))
def update_table(data):
    if data is None:
        return no_update
    return data


@callback(Output('memory-graph', 'figure'), Input('memory-output', 'data'), Input('memory-field', 'value'))
def update_graph(data, field):
    if data is None:
        return no_update
    dff = pd.DataFrame(data)
    fig = px.line(
        dff,
        x='year',
        y=field,
        color='country',
        markers=True,
        title=f'{field} over time'
    )
    return fig


if __name__ == '__main__':
    app.run(debug=True)
```

```python

from dash import Dash, html, dcc, Output, Input, State, callback, MATCH, no_update

# This example uses pattern matching callbacks since it needs 2 callbacks for each button.
# For more info see https://dash.plotly.com/pattern-matching-callbacks

app = Dash(__name__)

app.layout = html.Div([
    html.Div("Click to store in:"),

    # The memory store reverts to the default on every page refresh
    dcc.Store(id={'type': 'storage', 'index': 'memory'}),

    # The local store will take the initial data
    # only the first time the page is loaded
    # and keep it until it is cleared.
    dcc.Store(id={'type': 'storage', 'index': 'local'}, storage_type='local'),

    # Same as the local store but will lose the data
    # when the browser/tab closes.
    dcc.Store(id={'type': 'storage', 'index': 'session'}, storage_type='session'),

    html.Button('Memory Storage', id={'type': 'button-storage', 'index': 'memory'}),
    html.Button('Local Storage', id={'type': 'button-storage', 'index': 'local'}),
    html.Button('Session Storage', id={'type': 'button-storage', 'index': 'session'}),
    html.Hr(),

    html.Div([html.Span(0, id={'type': 'output-storage', 'index': 'memory'}), " Memory Clicks"]),
    html.Div([html.Span(0, id={'type': 'output-storage', 'index': 'local'}), " Local Clicks"]),
    html.Div([html.Span(0, id={'type': 'output-storage', 'index': 'session'}), " Session Clicks"]),
])


@callback(
    Output({'type': 'storage', 'index': MATCH}, 'data'),
    Input({'type': 'button-storage', 'index': MATCH}, 'n_clicks'),
    State({'type': 'storage', 'index': MATCH}, 'data'))
def on_click(n_clicks, data):
    if n_clicks is None:
        return no_update

    # Give a default data dict with 0 clicks if there's no data.
    data = data or {'clicks': 0}

    data['clicks'] = data['clicks'] + 1
    return data

# Since we use the data prop in an output, we cannot get the initial data on load with the data prop.
# Instead, we use the modified_timestamp as Input and the data as State.
@callback(
    Output({'type': 'output-storage', 'index': MATCH}, 'children'),
    Input({'type': 'storage', 'index': MATCH}, 'modified_timestamp'),
    State({'type': 'storage', 'index': MATCH}, 'data'))
def on_data(ts, data):
    if ts is None:
        return no_update
    data = data or {}
    return data.get('clicks', 0)


if __name__ == '__main__':
    app.run(debug=True)
```